WESTPAC BANKING CORP (SEC Filing Page | XBRL Cloud Viewer | XBRL Instance)

Line Label Object Class Period Type Balance Report ElementName
1 00090 - Document - Document and Entity Information Network

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 http://www.westpac.com.au/role/DocumentDocumentAndEntityInformation
2 Implied Table Table

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 implied:Table
3 Document and Entity Information [Abstract] Abstract wbk:DocumentAndEntityInformationAbstract
4 Entity Registrant Name Concept (Text/String) For Period dei:EntityRegistrantName
5 Entity Central Index Key Concept (CIK Number) For Period dei:EntityCentralIndexKey
6 Document Type Concept (Submission Type) For Period dei:DocumentType
7 Document Period End Date Concept (Date) For Period dei:DocumentPeriodEndDate
8 Amendment Flag Concept (Yes/No) For Period dei:AmendmentFlag
9 Amendment Description Concept (Text/String) For Period dei:AmendmentDescription
10 Current Fiscal Year End Date Concept (Month/Day) For Period dei:CurrentFiscalYearEndDate
11 Entity Well-known Seasoned Issuer Concept (Yes/No) For Period dei:EntityWellKnownSeasonedIssuer
12 Entity Voluntary Filers Concept (Yes/No) For Period dei:EntityVoluntaryFilers
13 Entity Current Reporting Status Concept (Yes/No) For Period dei:EntityCurrentReportingStatus
14 Entity Filer Category Concept (Filer Category) For Period dei:EntityFilerCategory
15 Entity Common Stock, Shares Outstanding Concept (Shares) As Of dei:EntityCommonStockSharesOutstanding
16 Document Fiscal Year Focus Concept (Year) For Period dei:DocumentFiscalYearFocus
17 Document Fiscal Period Focus Concept (Fiscal Period) For Period dei:DocumentFiscalPeriodFocus
18 00100 - Statement - Income statements Network

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 http://www.westpac.com.au/role/StatementIncomeStatements
19 Condensed Financial Statements [Table] Table

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 us-gaap:ScheduleOfCondensedFinancialStatementsTable
20 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
21 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
22 Parent Entity Member us-gaap:ParentCompanyMember
23 Condensed financial statements LineItems us-gaap:CondensedFinancialStatementsCaptionsLineItems
24 Income statements Abstract ifrs-full:ProfitLossAbstract
25 Interest income Concept (Monetary) For Period Credit ifrs-full:RevenueFromInterest
26 Interest expense Concept (Monetary) For Period Debit ifrs-full:InterestExpense
27 Net interest income Concept (Monetary) For Period Credit ifrs-full:InterestRevenueExpense
28 Non-interest income Concept (Monetary) For Period Credit wbk:IfrsNoninterestIncome
29 Net operating income before operating expenses and impairment charges Concept (Monetary) For Period Credit wbk:NetOperatingIncomeBeforeOperatingExpenseAndImpairmentCharges
30 Operating expenses Concept (Monetary) For Period Debit ifrs-full:OperatingExpense
31 Impairment charges Concept (Monetary) For Period Debit ifrs-full:ImpairmentLossReversalOfImpairmentLossRecognisedInProfitOrLossLoansAndAdvances
32 Profit before income tax Concept (Monetary) For Period Credit ifrs-full:ProfitLossBeforeTax
33 Income tax expense Concept (Monetary) For Period Debit ifrs-full:IncomeTaxExpenseContinuingOperations
34 Net profit for the year Concept (Monetary) For Period Credit ifrs-full:ProfitLoss
35 Net profit attributable to non-controlling interests Concept (Monetary) For Period Credit ifrs-full:ProfitLossAttributableToNoncontrollingInterests
36 Net profit attributable to owners of Westpac Banking Corporation Concept (Monetary) For Period Credit ifrs-full:ProfitLossAttributableToOwnersOfParent
37 Earnings per share Abstract ifrs-full:EarningsPerShareAbstract
38 Basic (in dollars per share) Concept (Share) For Period ifrs-full:BasicEarningsLossPerShare
39 Diluted (in dollars per share) Concept (Share) For Period ifrs-full:DilutedEarningsLossPerShare
40 00200 - Statement - Statements of comprehensive income Network

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 http://www.westpac.com.au/role/StatementStatementsOfComprehensiveIncome
41 Condensed Financial Statements [Table] Table

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 us-gaap:ScheduleOfCondensedFinancialStatementsTable
42 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
43 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
44 Parent Entity Member us-gaap:ParentCompanyMember
45 Condensed financial statements LineItems us-gaap:CondensedFinancialStatementsCaptionsLineItems
46 Statements of comprehensive income Abstract ifrs-full:ComprehensiveIncomeAbstract
47 Net profit for the year Concept (Monetary) For Period Credit ifrs-full:ProfitLoss
48 Other comprehensive income Abstract ifrs-full:OtherComprehensiveIncomeAbstract
49 Items that may be reclassified subsequently to profit or loss Abstract ifrs-full:ComponentsOfOtherComprehensiveIncomeThatWillBeReclassifiedToProfitOrLossNetOfTaxAbstract
50 Gains/(losses) on available-for-sale securities: Abstract ifrs-full:AvailableforsaleFinancialAssetsAbstract
51 Recognised in equity Concept (Monetary) For Period Credit ifrs-full:GainsLossesOnRemeasuringAvailableforsaleFinancialAssetsBeforeTax
52 Transferred to income statements Concept (Monetary) For Period Debit ifrs-full:ReclassificationAdjustmentsOnAvailableforsaleFinancialAssetsBeforeTax
53 Gains/(losses) on cash flow hedging instruments: Abstract ifrs-full:CashFlowHedgesAbstract
54 Recognised in equity Concept (Monetary) For Period Credit ifrs-full:GainsLossesOnCashFlowHedgesBeforeTax
55 Transferred to income statements Concept (Monetary) For Period Debit ifrs-full:ReclassificationAdjustmentsOnCashFlowHedgesBeforeTax
56 Movement in foreign currency translation reserve: Abstract ifrs-full:ExchangeDifferencesOnTranslationAbstract
57 Exchange differences on translation of foreign operations Concept (Monetary) For Period Credit ifrs-full:GainsLossesOnExchangeDifferencesOnTranslationNetOfTax
58 Transferred to income statements Concept (Monetary) For Period Debit ifrs-full:ReclassificationAdjustmentsOnExchangeDifferencesOnTranslationNetOfTax
59 Income tax on items taken to or transferred from equity: Abstract ifrs-full:IncomeTaxRelatingToComponentsOfOtherComprehensiveIncomeThatWillBeReclassifiedToProfitOrLossAbstract
60 Available-for-sale securities reserve Concept (Monetary) For Period Debit ifrs-full:IncomeTaxRelatingToAvailableforsaleFinancialAssetsOfOtherComprehensiveIncome
61 Cash flow hedge reserve Concept (Monetary) For Period Debit ifrs-full:IncomeTaxRelatingToCashFlowHedgesOfOtherComprehensiveIncome
62 Share of associates' other comprehensive income: Abstract ifrs-full:ShareOfOtherComprehensiveIncomeOfAssociatesAndJointVenturesAccountedForUsingEquityMethodNetOfTaxAbstract
63 Recognised in equity (net of tax) Concept (Monetary) For Period Credit ifrs-full:ShareOfOtherComprehensiveIncomeOfAssociatesAndJointVenturesAccountedForUsingEquityMethodThatWillBeReclassifiedToProfitOrLossNetOfTax
64 Transferred to income statements Concept (Monetary) For Period Debit wbk:ReclassificationAdjustmentOnShareOfOtherComprehensiveIncomeOfAssociatesAndJointVenturesAccountedForUsingEquityMethodNetOfTax
65 Items that will not be reclassified subsequently to profit or loss Abstract ifrs-full:ComponentsOfOtherComprehensiveIncomeThatWillNotBeReclassifiedToProfitOrLossNetOfTaxAbstract
66 Own credit adjustment on financial liabilities designated at fair value (net of tax) Concept (Monetary) For Period Credit ifrs-full:OtherComprehensiveIncomeNetOfTaxChangeInFairValueOfFinancialLiabilityAttributableToChangeInCreditRiskOfLiability
67 Remeasurement of defined benefit obligation recognised in equity (net of tax) Concept (Monetary) For Period Credit ifrs-full:OtherComprehensiveIncomeNetOfTaxGainsLossesOnRemeasurementsOfDefinedBenefitPlans
68 Other comprehensive income for the year (net of tax) Concept (Monetary) For Period Credit ifrs-full:OtherComprehensiveIncome
69 Total comprehensive income for the year Concept (Monetary) For Period Credit ifrs-full:ComprehensiveIncome
70 Attributable to: Abstract ifrs-full:ComprehensiveIncomeAttributableToAbstract
71 Owners of Westpac Banking Corporation Concept (Monetary) For Period Credit ifrs-full:ComprehensiveIncomeAttributableToOwnersOfParent
72 Non-controlling interests Concept (Monetary) For Period Credit ifrs-full:ComprehensiveIncomeAttributableToNoncontrollingInterests
73 Total comprehensive income for the year Concept (Monetary) For Period Credit ifrs-full:ComprehensiveIncome
74 00300 - Statement - Balance Sheets Network

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 http://www.westpac.com.au/role/StatementBalanceSheets
75 Condensed Financial Statements [Table] Table

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 us-gaap:ScheduleOfCondensedFinancialStatementsTable
76 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
77 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
78 Parent Entity Member us-gaap:ParentCompanyMember
79 Condensed financial statements LineItems us-gaap:CondensedFinancialStatementsCaptionsLineItems
80 Assets Abstract ifrs-full:AssetsAbstract
81 Cash and balances with central banks Concept (Monetary) As Of Debit ifrs-full:CashAndBankBalancesAtCentralBanks
82 Receivables due from other financial institutions Concept (Monetary) As Of Debit wbk:ReceivablesDueFromOtherFinancialInstitutions
83 Trading securities and financial assets designated at fair value Concept (Monetary) As Of Debit ifrs-full:FinancialAssetsAtFairValueThroughProfitOrLoss
84 Derivative financial instruments Concept (Monetary) As Of Debit ifrs-full:DerivativeFinancialAssets
85 Available-for-sale securities Concept (Monetary) As Of Debit ifrs-full:FinancialAssetsAvailableforsale
86 Loans Concept (Monetary) As Of Debit ifrs-full:LoansAndReceivables
87 Life insurance assets Concept (Monetary) As Of Debit wbk:LifeInsuranceAssets
88 Regulatory deposits with central banks overseas Concept (Monetary) As Of Debit ifrs-full:MandatoryReserveDepositsAtCentralBanks
89 Due from subsidiaries Concept (Monetary) As Of Debit ifrs-full:TradeAndOtherReceivablesDueFromRelatedParties
90 Investment in subsidiaries Concept (Monetary) As Of Debit ifrs-full:InvestmentsInSubsidiaries
91 Investment in associates Concept (Monetary) As Of Debit ifrs-full:InvestmentsInAssociates
92 Property and equipment Concept (Monetary) As Of Debit ifrs-full:PropertyPlantAndEquipment
93 Deferred tax assets Concept (Monetary) As Of Debit ifrs-full:NetDeferredTaxAssets
94 Intangible assets Concept (Monetary) As Of Debit ifrs-full:IntangibleAssetsAndGoodwill
95 Other assets Concept (Monetary) As Of Debit ifrs-full:OtherAssets
96 Total assets Concept (Monetary) As Of Debit ifrs-full:Assets
97 Liabilities Abstract ifrs-full:LiabilitiesAbstract
98 Payables due to other financial institutions Concept (Monetary) As Of Credit wbk:PayablesDueToOtherFinancialInstitutions
99 Deposits and other borrowings Concept (Monetary) As Of Credit wbk:DepositsAndOtherBorrowings
100 Other financial liabilities at fair value through income statement Concept (Monetary) As Of Credit ifrs-full:FinancialLiabilitiesAtFairValueThroughProfitOrLoss
101 Derivative financial instruments Concept (Monetary) As Of Credit ifrs-full:DerivativeFinancialLiabilities
102 Debt issues Concept (Monetary) As Of Credit ifrs-full:DebtSecurities
103 Current tax liabilities Concept (Monetary) As Of Credit ifrs-full:CurrentTaxLiabilities
104 Life insurance liabilities Concept (Monetary) As Of Credit ifrs-full:LiabilitiesArisingFromInsuranceContracts
105 Due to subsidiaries Concept (Monetary) As Of Credit ifrs-full:TradeAndOtherPayablesToRelatedParties
106 Provisions Concept (Monetary) As Of Credit ifrs-full:Provisions
107 Deferred tax liabilities Concept (Monetary) As Of Credit ifrs-full:NetDeferredTaxLiabilities
108 Other liabilities Concept (Monetary) As Of Credit ifrs-full:OtherLiabilities
109 Total liabilities excluding loan capital Concept (Monetary) As Of Credit wbk:LiabilitiesExcludingLoanCapital
110 Loan capital Concept (Monetary) As Of Credit wbk:LoanCapital
111 Total liabilities Concept (Monetary) As Of Credit ifrs-full:Liabilities
112 Net assets/(net liabilities) Concept (Monetary) As Of Debit ifrs-full:NetAssetsLiabilities
113 Shareholders' equity Abstract ifrs-full:EquityAbstract
114 Share capital: Abstract wbk:ShareCapitalAbstract
115 Ordinary share capital Concept (Monetary) As Of Credit ifrs-full:IssuedCapital
116 Treasury shares and RSP treasury shares Concept (Monetary) As Of Debit ifrs-full:TreasuryShares
117 Reserves Concept (Monetary) As Of Credit ifrs-full:OtherReserves
118 Retained profits Concept (Monetary) As Of Credit ifrs-full:RetainedEarnings
119 Total equity attributable to owners of Westpac Banking Corporation Concept (Monetary) As Of Credit ifrs-full:EquityAttributableToOwnersOfParent
120 Non-controlling interests Concept (Monetary) As Of Credit ifrs-full:NoncontrollingInterests
121 Total shareholders' equity and non-controlling interests Concept (Monetary) As Of Credit ifrs-full:Equity
122 00400 - Statement - Statements of changes in equity Network

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 http://www.westpac.com.au/role/StatementStatementsOfChangesInEquity
123 Statement of changes in equity [table] Table

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 ifrs-full:StatementOfChangesInEquityTable
124 Components of equity [axis] Axis ifrs-full:ComponentsOfEquityAxis
125 Equity [member] Member ifrs-full:EquityMember
126 Total equity attributable to owners of Westpac Banking Corporation Member ifrs-full:EquityAttributableToOwnersOfParentMember
127 Share capital Member ifrs-full:IssuedCapitalMember
128 Reserves Member ifrs-full:OtherReservesMember
129 Retained profits Member ifrs-full:RetainedEarningsMember
130 Non-controlling interests Member ifrs-full:NoncontrollingInterestsMember
131 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
132 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
133 Parent Entity Member us-gaap:ParentCompanyMember
134 Statements of changes in equity LineItems ifrs-full:StatementOfChangesInEquityLineItems
135 Balance at the beginning of period Concept (Monetary) As Of Credit ifrs-full:Equity
136 Net profit for the year Concept (Monetary) For Period Credit ifrs-full:ProfitLoss
137 Net other comprehensive income for the year Concept (Monetary) For Period Credit ifrs-full:OtherComprehensiveIncome
138 Total comprehensive income for the year Concept (Monetary) For Period Credit ifrs-full:ComprehensiveIncome
139 Dividends on ordinary shares Concept (Monetary) For Period Debit ifrs-full:DividendsPaid
140 Dividend reinvestment plan Concept (Monetary) For Period Credit wbk:IfrsStockIssuedDuringPeriodValueDividendReinvestmentPlan
141 Share entitlement offer Concept (Monetary) For Period Credit ifrs-full:IssueOfEquity
142 Conversion of Convertible Preference Shares Concept (Monetary) For Period Credit ifrs-full:IncreaseDecreaseThroughConversionOfConvertibleInstruments
143 Share based payment arrangements Concept (Monetary) For Period Credit ifrs-full:IncreaseDecreaseThroughSharebasedPaymentTransactions
144 Exercise of employee share options and rights Concept (Monetary) For Period Credit ifrs-full:IncreaseDecreaseThroughExerciseOfOptions
145 Purchase of shares (net of issue costs) Concept (Monetary) For Period Debit wbk:DecreaseThroughAcquisitionOrRedemptionOfEntitysSharesNetOfIssueCost
146 Net (acquisition)/disposal of treasury shares Concept (Monetary) For Period Credit ifrs-full:IncreaseDecreaseThroughTreasuryShareTransactions
147 Other Concept (Monetary) For Period Credit ifrs-full:IncreaseDecreaseThroughTransfersAndOtherChangesEquity
148 Total contributions and distributions Concept (Monetary) For Period Credit ifrs-full:ChangesInEquity
149 Balance at the end of period Concept (Monetary) As Of Credit ifrs-full:Equity
150 00405 - Statement - Statements of changes in equity (Parenthetical) Network

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 http://www.westpac.com.au/role/StatementStatementsOfChangesInEquityParenthetical
151 Statement of changes in equity [table] Table

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 ifrs-full:StatementOfChangesInEquityTable
152 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
153 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
154 Parent Entity Member us-gaap:ParentCompanyMember
155 Statements of changes in equity LineItems ifrs-full:StatementOfChangesInEquityLineItems
156 Interim dividend (in dollars per share) Concept (Share) For Period wbk:DividendsPaidOrdinarySharesPerShareRelatingToCurrentYear
157 Interim dividend Concept (Monetary) For Period Debit ifrs-full:DividendsRecognisedAsDistributionsToOwnersOfParentRelatingToCurrentYear
158 Final dividend (in dollars per share) Concept (Share) For Period wbk:DividendsPaidOrdinarySharesPerShareRelatingToPriorYears
159 Final dividend Concept (Monetary) For Period Debit ifrs-full:DividendsRecognisedAsDistributionsToOwnersOfParentRelatingToPriorYears
160 Dividend tax rate (as a percent) Concept (Percent) For Period wbk:RateOfDividendDistributionTax
161 00500 - Statement - Cash flow statements Network

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 http://www.westpac.com.au/role/StatementCashFlowStatements
162 Condensed Financial Statements [Table] Table

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 us-gaap:ScheduleOfCondensedFinancialStatementsTable
163 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
164 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
165 Parent Entity Member us-gaap:ParentCompanyMember
166 Condensed financial statements LineItems us-gaap:CondensedFinancialStatementsCaptionsLineItems
167 Cash flows from operating activities Abstract ifrs-full:CashFlowsFromUsedInOperatingActivitiesAbstract
168 Interest received Concept (Monetary) For Period Debit ifrs-full:InterestReceivedClassifiedAsOperatingActivities
169 Interest paid Concept (Monetary) For Period Credit ifrs-full:InterestPaidClassifiedAsOperatingActivities
170 Dividends received excluding life business Concept (Monetary) For Period Debit wbk:DividendsReceivedClassifiedAsOperatingActivitiesExcludingLifeBusiness
171 Other non-interest income received Concept (Monetary) For Period Debit ifrs-full:ReceiptsFromRoyaltiesFeesCommissionsAndOtherRevenue
172 Operating expenses paid Concept (Monetary) For Period Credit ifrs-full:PaymentsToSuppliersForGoodsAndServicesAndToAndOnBehalfOfEmployees
173 Income tax paid excluding life business Concept (Monetary) For Period Credit wbk:IncomeTaxesPaidClassifiedAsOperatingActivitiesExcludingLifeBusiness
174 Life business: Abstract wbk:LifeBusinessAbstract
175 Receipts from policyholders and customers Concept (Monetary) For Period Debit ifrs-full:ReceiptsFromPremiumsAndClaimsAnnuitiesAndOtherPolicyBenefits
176 Interest and other items of similar nature Concept (Monetary) For Period Debit wbk:ReceiptsFromInterestAndSimilarItemsRelatedToLifeBusiness
177 Dividends received Concept (Monetary) For Period Debit wbk:DividendsReceivedClassifiedAsOperatingActivitiesLifeBusiness
178 Payments to policyholders and suppliers Concept (Monetary) For Period Credit ifrs-full:PaymentsForPremiumsAndClaimsAnnuitiesAndOtherPolicyBenefits
179 Income tax paid Concept (Monetary) For Period Credit wbk:IncomeTaxesPaidClassifiedAsOperatingActivitiesLifeBusiness
180 Cash flows from operating activities before changes in operating assets and liabilities Concept (Monetary) For Period ifrs-full:CashFlowsFromUsedInOperationsBeforeChangesInWorkingCapital
181 Net (increase)/decrease in: Abstract wbk:NetIncreaseDecreaseInAssetsOperatingActivitiesAbstract
182 Trading securities and financial assets designated at fair value Concept (Monetary) For Period Debit wbk:AdjustmentsForDecreaseIncreaseInFinancialAssetsAtFairValueThroughProfitOrLoss
183 Loans Concept (Monetary) For Period Debit wbk:AdjustmentsForDecreaseIncreaseInLoansAndReceivables
184 Receivables due from other financial institutions Concept (Monetary) For Period Debit wbk:AdjustmentsForDecreaseIncreaseInReceivablesDueFromOtherFinancialInstitutions
185 Life insurance assets and liabilities Concept (Monetary) For Period Debit wbk:AdjustmentsForDecreaseIncreaseInLifeInsuranceAssetsAndLiabilities
186 Regulatory deposits with central banks overseas Concept (Monetary) For Period Debit wbk:AdjustmentsForDecreaseIncreaseInMandatoryReserveDepositsAtCentralBanks
187 Derivative financial instruments Concept (Monetary) For Period Debit wbk:AdjustmentsForDecreaseIncreaseInDerivativeFinancialInstruments
188 Other assets Concept (Monetary) For Period Debit ifrs-full:AdjustmentsForDecreaseIncreaseInOtherAssets
189 Net increase/(decrease) in: Abstract wbk:NetIncreaseDecreaseInLiabilitiesOperatingActivitiesAbstract
190 Other financial liabilities at fair value through income statement Concept (Monetary) For Period Debit wbk:AdjustmentsForIncreaseDecreaseInFinancialLiabilitiesAtFairValueThroughProfitOrLoss
191 Deposits and other borrowings Concept (Monetary) For Period Debit wbk:AdjustmentsForIncreaseDecreaseInDepositsAndOtherBorrowings
192 Payables due to other financial institutions Concept (Monetary) For Period Debit wbk:AdjustmentsForIncreaseDecreaseInPayablesDueToOtherFinancialInstitutions
193 Other liabilities Concept (Monetary) For Period Debit ifrs-full:AdjustmentsForIncreaseDecreaseInOtherLiabilities
194 Net cash provided by/(used in) operating activities Concept (Monetary) For Period ifrs-full:CashFlowsFromUsedInOperatingActivities
195 Cash flows from investing activities Abstract ifrs-full:CashFlowsFromUsedInInvestingActivitiesAbstract
196 Proceeds from available-for-sale securities Concept (Monetary) For Period Debit ifrs-full:ProceedsFromDisposalOrMaturityOfAvailableforsaleFinancialAssets
197 Purchase of available-for-sale securities Concept (Monetary) For Period Credit ifrs-full:PurchaseOfAvailableforsaleFinancialAssets
198 Net movement in amounts due to/from controlled entities Concept (Monetary) For Period Debit wbk:ProceedsPaymentsFromChangesInReceivablesDueFromAndPayablesDueToRelatedParties
199 Proceeds/(Payments) on disposal of controlled entities, net of cash disposed Concept (Monetary) For Period Debit ifrs-full:CashFlowsFromLosingControlOfSubsidiariesOrOtherBusinessesClassifiedAsInvestingActivities
200 Net (increase)/decrease in investments in controlled entities Concept (Monetary) For Period Debit wbk:ProceedsPaymentsFromChangesInOwnershipInterestsInSubsidiariesThatDoNotResultInLossOfControl
201 Proceeds from sale of associates Concept (Monetary) For Period Debit ifrs-full:ProceedsFromSalesOfInterestsInAssociates
202 Purchase of associates Concept (Monetary) For Period Credit ifrs-full:PurchaseOfInterestsInAssociates
203 Proceeds from disposal of property and equipment Concept (Monetary) For Period Debit ifrs-full:ProceedsFromSalesOfPropertyPlantAndEquipmentClassifiedAsInvestingActivities
204 Purchase of property and equipment Concept (Monetary) For Period Credit ifrs-full:PurchaseOfPropertyPlantAndEquipmentClassifiedAsInvestingActivities
205 Purchase of intangible assets Concept (Monetary) For Period Credit ifrs-full:PurchaseOfIntangibleAssetsClassifiedAsInvestingActivities
206 Net cash provided by/(used in) investing activities Concept (Monetary) For Period Debit ifrs-full:CashFlowsFromUsedInInvestingActivities
207 Cash flows from financing activities Abstract ifrs-full:CashFlowsFromUsedInFinancingActivitiesAbstract
208 Issue of loan capital (net of issue costs) Concept (Monetary) For Period Debit wbk:ProceedsFromIssueOfLoanCapitalNetOfIssueCosts
209 Redemption of loan capital Concept (Monetary) For Period Credit wbk:RedemptionOfLoanCapital
210 Net increase/(decrease) in debt issues Concept (Monetary) For Period Debit wbk:ProceedsFromIssueRepaymentsOfDebtInstruments
211 Proceeds from Share Entitlement Offer Concept (Monetary) For Period Debit ifrs-full:ProceedsFromIssueOfOrdinaryShares
212 Proceeds from exercise of employee options Concept (Monetary) For Period Debit ifrs-full:ProceedsFromExerciseOfOptions
213 Purchase of shares on exercise of employee options and rights Concept (Monetary) For Period Credit wbk:PaymentsToAcquireOrRedeemEntitysSharesForExerciseOfOptionsAndRights
214 Shares purchased for delivery of employee share plan Concept (Monetary) For Period Credit wbk:PaymentsToAcquireOrRedeemEntitysSharesForEmployeeSharePlan
215 Purchase of RSP treasury shares Concept (Monetary) For Period Credit wbk:PaymentsToAcquireOrRedeemEntitysSharesForRestrictedSharePlan
216 Net sale/(purchase) of other treasury shares Concept (Monetary) For Period Credit wbk:PaymentsToAcquireOrRedeemProceedsFromReissuanceOfOtherTreasuryShares
217 Payment of dividends Concept (Monetary) For Period Credit ifrs-full:DividendsPaidClassifiedAsFinancingActivities
218 Payment of distributions to non-controlling interests Concept (Monetary) For Period Credit ifrs-full:DividendsPaidToNoncontrollingInterestsClassifiedAsFinancingActivities
219 Redemption of 2006 Trust Preferred Securities Concept (Monetary) For Period Credit wbk:IfrsPaymentsForRepurchaseOfTrustPreferredSecurities
220 Net cash provided by/(used in) financing activities Concept (Monetary) For Period Debit ifrs-full:CashFlowsFromUsedInFinancingActivities
221 Net increase/(decrease) in cash and cash equivalents Concept (Monetary) For Period Debit ifrs-full:IncreaseDecreaseInCashAndCashEquivalentsBeforeEffectOfExchangeRateChanges
222 Effect of exchange rate changes on cash and cash equivalents Concept (Monetary) For Period Debit ifrs-full:EffectOfExchangeRateChangesOnCashAndCashEquivalents
223 Cash and cash equivalents as at the beginning of the year Concept (Monetary) As Of Debit ifrs-full:CashAndCashEquivalents
224 Cash and cash equivalents as at the end of the year Concept (Monetary) As Of Debit ifrs-full:CashAndCashEquivalents
225 10101 - Disclosure - Financial statements preparation Network

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226 Implied Table Table

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227 Financial statements preparation Abstract wbk:FinancialStatementsPreparationAbstract
228 Financial statements preparation Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfBasisOfPreparationOfFinancialStatementsExplanatory
229 10201 - Disclosure - Segment reporting Network

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230 Implied Table Table

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231 Segment reporting Abstract ifrs-full:DisclosureOfOperatingSegmentsAbstract
232 Segment reporting Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfEntitysReportableSegmentsExplanatory
233 10301 - Disclosure - Net interest income Network

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234 Implied Table Table

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235 Net interest income Abstract wbk:InterestIncomeAndExpensesAbstract
236 Net interest income Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfInterestIncomeExpenseExplanatory
237 10401 - Disclosure - Non-interest income Network

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238 Implied Table Table

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239 Non-interest income Abstract wbk:IfrsNonInterestIncomeAbstract
240 Non-interest income Concept (Text Block (HTML)) For Period wbk:DisclosureOfNonInterestIncomeTextBlock
241 10501 - Disclosure - Operating expenses Network

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242 Implied Table Table

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243 Operating expenses Abstract wbk:IfrsOperatingExpensesAbstract
244 Operating expenses Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfExpensesExplanatory
245 10601 - Disclosure - Impairment charges Network

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246 Implied Table Table

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247 Impairment charges Abstract ifrs-full:DisclosureOfImpairmentLossAndReversalOfImpairmentLossAbstract
248 Impairment charges Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfImpairmentOfAssetsExplanatory
249 10701 - Disclosure - Income tax Network

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250 Implied Table Table

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251 Income tax Abstract ifrs-full:MajorComponentsOfTaxExpenseIncomeAbstract
252 Income tax Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfIncomeTaxExplanatory
253 10801 - Disclosure - Earnings per share Network

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254 Implied Table Table

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255 Earnings per share Abstract ifrs-full:EarningsPerShareAbstract
256 Earnings per share Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfEarningsPerShareExplanatory
257 10901 - Disclosure - Average balance sheet and interest rates Network

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258 Implied Table Table

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259 Average balance sheet and interest rates Abstract wbk:AverageBalanceSheetAndInterestRatesAbstract
260 Average balance sheet and interest rates Concept (Text Block (HTML)) For Period wbk:AverageBalancesAndInterestRatesTextBlock
261 11000 - Disclosure - Financial Assets and Financial Liabilities Network

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262 Implied Table Table

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263 Financial Assets and Financial Liabilities Abstract wbk:FinancialAssetsAndFinancialLiabilitiesPolicyDisclosureAbstract
264 Financial Assets and Financial Liabilities Concept (Text Block (HTML)) For Period wbk:FinancialAssetsAndFinancialLiabilitiesPolicyDisclosureTextBlock
265 11001 - Disclosure - Receivables due from other financial institutions Network

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266 Implied Table Table

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267 Receivables due from other financial institutions Abstract wbk:ReceivablesDueFromOtherFinancialInstitutionsAbstract
268 Receivables due from other financial institutions Concept (Text Block (HTML)) For Period wbk:ReceivablesDueFromOtherFinancialInstitutionsTextBlock
269 11101 - Disclosure - Trading securities and financial assets designated at fair value Network

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 http://www.westpac.com.au/role/DisclosureTradingSecuritiesAndFinancialAssetsDesignatedAtFairValue
270 Implied Table Table

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 implied:Table
271 Trading securities and financial assets designated at fair value Abstract wbk:DisclosureOfTradingSecuritiesAndFinancialAssetsDesignatedAtFairValueAbstract
272 Trading securities and financial assets designated at fair value Concept (Text Block (HTML)) For Period wbk:DisclosureOfTradingSecuritiesAndFinancialAssetsDesignatedAtFairValueTextBlock
273 11201 - Disclosure - Available-for-sale securities Network

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*

 http://www.westpac.com.au/role/DisclosureAvailableForSaleSecurities
274 Implied Table Table

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 implied:Table
275 Available-for-sale securities Abstract wbk:DisclosureOfAvailableForSaleSecuritiesAbstract
276 Available-for-sale securities Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfAvailableforsaleAssetsExplanatory
277 11301 - Disclosure - Loans Network

*

*

 http://www.westpac.com.au/role/DisclosureLoans
278 Implied Table Table

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*

 implied:Table
279 Loans Abstract wbk:DisclosureOfLoansAndAdvancesToCustomersAbstract
280 Loans Concept (Text Block (HTML)) For Period wbk:DisclosureOfLoansAndFinanceLeasesTextBlock
281 11401 - Disclosure - Provisions for impairment charges Network

*

*

 http://www.westpac.com.au/role/DisclosureProvisionsForImpairmentCharges
282 Implied Table Table

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*

 implied:Table
283 Provisions for impairment charges Abstract wbk:DisclosureOfProvisionsForImpairmentChargesAbstract
284 Provisions for impairment charges Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfAllowanceForCreditLossesExplanatory
285 11501 - Disclosure - Life insurance assets and life insurance liabilities Network

*

*

 http://www.westpac.com.au/role/DisclosureLifeInsuranceAssetsAndLifeInsuranceLiabilities
286 Implied Table Table

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*

 implied:Table
287 Life insurance assets and life insurance liabilities Abstract wbk:DisclosureOfInsuranceContractsAbstract
288 Life insurance assets and life insurance liabilities Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfInsuranceContractsExplanatory
289 11601 - Disclosure - Payables due to other financial institutions Network

*

*

 http://www.westpac.com.au/role/DisclosurePayablesDueToOtherFinancialInstitutions
290 Implied Table Table

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*

 implied:Table
291 Payables due to other financial institutions Abstract ifrs-full:TradeAndOtherPayablesAbstract
292 Payables due to other financial institutions Concept (Text Block (HTML)) For Period wbk:PayablesDueToOtherFinancialInstitutionsTextBlock
293 11701 - Disclosure - Deposits and other borrowings Network

*

*

 http://www.westpac.com.au/role/DisclosureDepositsAndOtherBorrowings
294 Implied Table Table

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*

 implied:Table
295 Deposits and other borrowings Abstract wbk:DisclosureOfDepositsAndOtherBorrowingsAbstract
296 Deposits and other borrowings Concept (Text Block (HTML)) For Period wbk:DisclosureOfDepositsAndOtherBorrowingsTextBlock
297 11801 - Disclosure - Other financial liabilities at fair value through income statement Network

*

*

 http://www.westpac.com.au/role/DisclosureOtherFinancialLiabilitiesAtFairValueThroughIncomeStatement
298 Implied Table Table

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 implied:Table
299 Other financial liabilities at fair value through income statement Abstract ifrs-full:FinancialLiabilitiesAtFairValueThroughProfitOrLossAbstract
300 Other financial liabilities at fair value through income statement Concept (Text Block (HTML)) For Period wbk:DisclosureOfOtherFinancialLiabilitiesAtFairValueThroughProfitOrLossTextBlock
301 11901 - Disclosure - Debt issues Network

*

*

 http://www.westpac.com.au/role/DisclosureDebtIssues
302 Implied Table Table

*

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 implied:Table
303 Debt issues Abstract ifrs-full:BorrowingCostsAbstract
304 Debt issues Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsExplanatory
305 12001 - Disclosure - Loan Capital Network

*

*

 http://www.westpac.com.au/role/DisclosureLoanCapital
306 Implied Table Table

*

*

 implied:Table
307 Loan Capital Abstract wbk:DisclosureOfLoanCapitalAbstract
308 Loan Capital Concept (Text Block (HTML)) For Period wbk:DisclosureOfLoanCapitalTextBlock
309 12101 - Disclosure - Derivative financial instruments Network

*

*

 http://www.westpac.com.au/role/DisclosureDerivativeFinancialInstruments
310 Implied Table Table

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 implied:Table
311 Derivative financial instruments Abstract ifrs-full:DisclosureOfFinancialInstrumentsAbstract
312 Derivative financial instruments Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfDerivativeFinancialInstrumentsExplanatory
313 12201 - Disclosure - Financial risk Network

*

*

 http://www.westpac.com.au/role/DisclosureFinancialRisk
314 Implied Table Table

*

*

 implied:Table
315 Financial risk Abstract wbk:FinancialRiskAbstract
316 Financial risk Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfFinancialRiskManagementExplanatory
317 12301 - Disclosure - Fair values of financial assets and financial liabilities Network

*

*

 http://www.westpac.com.au/role/DisclosureFairValuesOfFinancialAssetsAndFinancialLiabilities
318 Implied Table Table

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*

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319 Fair values of financial assets and financial liabilities Abstract wbk:DisclosureOfFairValueMeasurementAbstract
320 Fair values of financial assets and financial liabilities Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfFairValueMeasurementExplanatory
321 12401 - Disclosure - Offsetting financial assets and financial liabilities Network

*

*

 http://www.westpac.com.au/role/DisclosureOffsettingFinancialAssetsAndFinancialLiabilities
322 Implied Table Table

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*

 implied:Table
323 Offsetting financial assets and financial liabilities Abstract wbk:DisclosureOfOffsettingOfFinancialAssetsAndFinancialLiabilitiesAbstract
324 Offsetting financial assets and financial liabilities Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfOffsettingOfFinancialAssetsAndFinancialLiabilitiesExplanatory
325 12501 - Disclosure - Securitisation, covered bonds and other transferred assets Network

*

*

 http://www.westpac.com.au/role/DisclosureSecuritisationCoveredBondsAndOtherTransferredAssets
326 Implied Table Table

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327 Securitisation, covered bonds and other transferred assets Abstract ifrs-full:DisclosureOfFinancialAssetsTransferredDuringPeriodWhichDoNotQualifyForDerecognitionAbstract
328 Securitisation, covered bonds and other transferred assets Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfTransfersOfFinancialAssetsExplanatory
329 12601 - Disclosure - Intangible assets Network

*

*

 http://www.westpac.com.au/role/DisclosureIntangibleAssets
330 Implied Table Table

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 implied:Table
331 Intangible assets Abstract ifrs-full:IntangibleAssetsAndGoodwillAbstract
332 Intangible assets Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfIntangibleAssetsExplanatory
333 12701 - Disclosure - Other assets Network

*

*

 http://www.westpac.com.au/role/DisclosureOtherAssets
334 Implied Table Table

*

*

 implied:Table
335 Other assets Abstract ifrs-full:MiscellaneousAssetsAbstract
336 Other assets Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfOtherAssetsExplanatory
337 12801 - Disclosure - Provisions Network

*

*

 http://www.westpac.com.au/role/DisclosureProvisions
338 Implied Table Table

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 implied:Table
339 Provisions Abstract ifrs-full:ProvisionsAbstract
340 Provisions Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfProvisionsExplanatory
341 12901 - Disclosure - Other liabilities Network

*

*

 http://www.westpac.com.au/role/DisclosureOtherLiabilities
342 Implied Table Table

*

*

 implied:Table
343 Other liabilities Abstract ifrs-full:MiscellaneousLiabilitiesAbstract
344 Other liabilities Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfOtherLiabilitiesExplanatory
345 13001 - Disclosure - Operating lease commitments Network

*

*

 http://www.westpac.com.au/role/DisclosureOperatingLeaseCommitments
346 Implied Table Table

*

*

 implied:Table
347 Operating lease commitments Abstract wbk:OperatingLeaseCommitmentsAbstract
348 Operating lease commitments Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfFinanceLeaseAndOperatingLeaseByLesseeExplanatory
349 13101 - Disclosure - Contingent liabilities, contingent assets and credit commitments Network

*

*

 http://www.westpac.com.au/role/DisclosureContingentLiabilitiesContingentAssetsAndCreditCommitments
350 Implied Table Table

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 implied:Table
351 Contingent liabilities, contingent assets and credit commitments Abstract ifrs-full:DisclosureOfContingentLiabilitiesAbstract
352 Contingent liabilities, contingent assets and credit commitments Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfCommitmentsAndContingentLiabilitiesExplanatory
353 13201 - Disclosure - Shareholders' equity Network

*

*

 http://www.westpac.com.au/role/DisclosureShareholdersEquity
354 Implied Table Table

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355 Shareholders' equity Abstract ifrs-full:DisclosureOfClassesOfShareCapitalAbstract
356 Shareholders' equity Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfShareCapitalReservesAndOtherEquityInterestExplanatory
357 13301 - Disclosure - Capital adequacy Network

*

*

 http://www.westpac.com.au/role/DisclosureCapitalAdequacy
358 Implied Table Table

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359 Capital adequacy Abstract wbk:DisclosureOfRegulatoryCapitalRequirementsUnderBankingRegulationsAbstract
360 Capital adequacy Concept (Text Block (HTML)) For Period wbk:DisclosureOfCapitalAdequacyTextBlock
361 13401 - Disclosure - Dividends Network

*

*

 http://www.westpac.com.au/role/DisclosureDividends
362 Implied Table Table

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 implied:Table
363 Dividends Abstract wbk:DisclosureOfDividendsAbstract
364 Dividends Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfDividendsExplanatory
365 13501 - Disclosure - Investments in subsidiaries and associates Network

*

*

 http://www.westpac.com.au/role/DisclosureInvestmentsInSubsidiariesAndAssociates
366 Implied Table Table

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367 Investments in subsidiaries and associates Abstract ifrs-full:InvestmentsInSubsidiariesJointVenturesAndAssociatesAbstract
368 Investments in subsidiaries and associates Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfInterestsInOtherEntitiesExplanatory
369 13601 - Disclosure - Structured entities Network

*

*

 http://www.westpac.com.au/role/DisclosureStructuredEntities
370 Implied Table Table

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371 Structured entities Abstract wbk:DisclosureOfInformationAboutStructuredEntitiesAbstract
372 Structured entities Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfInformationAboutInterestsInStructuredEntityExplanatory
373 13701 - Disclosure - Share-based payments Network

*

*

 http://www.westpac.com.au/role/DisclosureShareBasedPayments
374 Implied Table Table

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*

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375 Share-based payments Abstract ifrs-full:DisclosureOfTermsAndConditionsOfSharebasedPaymentArrangementAbstract
376 Share-based payments Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfSharebasedPaymentArrangementsExplanatory
377 13801 - Disclosure - Superannuation commitments Network

*

*

 http://www.westpac.com.au/role/DisclosureSuperannuationCommitments
378 Implied Table Table

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379 Superannuation commitments Abstract ifrs-full:DisclosureOfDefinedBenefitPlansAbstract
380 Superannuation commitments Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfEmployeeBenefitsExplanatory
381 13901 - Disclosure - Auditor's remuneration Network

*

*

 http://www.westpac.com.au/role/DisclosureAuditorSRemuneration
382 Implied Table Table

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*

 implied:Table
383 Auditor's remuneration Abstract ifrs-full:AuditorsRemunerationAbstract
384 Auditor's remuneration Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfAuditorsRemunerationExplanatory
385 14001 - Disclosure - Related party disclosures Network

*

*

 http://www.westpac.com.au/role/DisclosureRelatedPartyDisclosures
386 Implied Table Table

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 implied:Table
387 Related party disclosures Abstract ifrs-full:DisclosureOfTransactionsBetweenRelatedPartiesAbstract
388 Related party disclosures Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfRelatedPartyExplanatory
389 14101 - Disclosure - Notes to the cash flow statements Network

*

*

 http://www.westpac.com.au/role/DisclosureNotesToCashFlowStatements
390 Implied Table Table

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 implied:Table
391 Notes to the cash flow statements Abstract wbk:NotesToCashFlowStatementsAbstract
392 Notes to the cash flow statements Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfCashFlowStatementExplanatory
393 14201 - Disclosure - Subsequent events Network

*

*

 http://www.westpac.com.au/role/DisclosureSubsequentEvents
394 Implied Table Table

*

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395 Subsequent events Abstract ifrs-full:DisclosureOfNonadjustingEventsAfterReportingPeriodAbstract
396 Subsequent events Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfEventsAfterReportingPeriodExplanatory
397 20102 - Disclosure - Financial statements preparation (Policies) Network

*

*

 http://www.westpac.com.au/role/DisclosureFinancialStatementsPreparationPolicies
398 Implied Table Table

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399 Financial statements preparation Abstract wbk:FinancialStatementsPreparationAbstract
400 Basis of accounting Concept (Text Block (HTML)) For Period wbk:DescriptionOfAccountingPolicyForBasisOfAccountingPolicyTextBlock
401 Historical cost convention Concept (Text Block (HTML)) For Period wbk:DescriptionOfAccountingPolicyForHistoricalCostConventionPolicyTextBlock
402 Comparative revisions Concept (Text Block (HTML)) For Period wbk:DescriptionOfAccountingPolicyForComparativeRevisionsPolicyTextBlock
403 Standards adopted during the year ended 30 September 2018 Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfInitialApplicationOfStandardsOrInterpretations
404 Business combinations Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForBusinessCombinationsExplanatory
405 Foreign currency translation Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForForeignCurrencyTranslationExplanatory
406 Critical accounting assumptions and estimates Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfAccountingJudgementsAndEstimatesExplanatory
407 Future developments in accounting standards Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfExpectedImpactOfInitialApplicationOfNewStandardsOrInterpretations
408 Financial Assets and Financial Liabilities Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForFinancialInstrumentsExplanatory
409 Segment reporting Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForSegmentReportingExplanatory
410 Net interest income Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForInterestIncomeAndExpenseExplanatory
411 Non-interest income Concept (Text Block (HTML)) For Period wbk:DescriptionOfAccountingPolicyForNonInterestIncomePolicyTextBlock
412 Impairment charges Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForImpairmentOfAssetsExplanatory
413 Income tax Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForIncomeTaxExplanatory
414 Earnings per share Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForEarningsPerShareExplanatory
415 Receivables due from other financial institutions Concept (Text Block (HTML)) For Period wbk:ReceivablesDueFromOtherFinancialInstitutionsPolicyTextBlock
416 Trading securities and financial assets designated at fair value Concept (Text Block (HTML)) For Period wbk:DescriptionOfAccountingPolicyForTradingSecuritiesAndFinancialAssetsDesignatedAtFairValuePolicyTextBlock
417 Available-for-sale securities Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForAvailableforsaleFinancialAssetsExplanatory
418 Loans Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForLoansAndReceivablesExplanatory
419 Provisions for impairment charges Concept (Text Block (HTML)) For Period wbk:DescriptionOfAccountingPolicyForProvisionsForImpairmentChargesPolicyTextBlock
420 Life insurance assets and life insurance liabilities Concept (Text Block (HTML)) For Period wbk:LifeInsuranceAssetsAndLifeInsuranceLiabilitiesPolicyTextBlock
421 Payables due to other financial institutions Concept (Text Block (HTML)) For Period wbk:PayablesDueToOtherFinancialInstitutionsPolicyTextBlock
422 Deposits and other borrowings Concept (Text Block (HTML)) For Period wbk:DescriptionOfAccountingPolicyForDepositsAndOtherBorrowingsPolicyTextBlock
423 Other financial liabilities at fair value through income statement Concept (Text Block (HTML)) For Period wbk:DescriptionOfAccountingPolicyForOtherFinancialLiabilitiesAtFairValueThroughIncomeStatementPolicyTextBlock
424 Debt issues Concept (Text Block (HTML)) For Period wbk:DebtSecuritiesIssuancesPolicyTextBlock
425 Loan Capital Concept (Text Block (HTML)) For Period wbk:DescriptionOfAccountingPolicyForLoanCapitalPolicyTextBlock
426 Derivative financial instruments Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForDerivativeFinancialInstrumentsAndHedgingExplanatory
427 Fair values of financial assets and financial liabilities Concept (Text Block (HTML)) For Period wbk:DescriptionOfAccountingPolicyForFairValuesOfFinancialAssetsAndFinancialLiabilitiesPolicyTextBlock
428 Offsetting financial assets and financial liabilities Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForOffsettingOfFinancialInstrumentsExplanatory
429 Intangible assets Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForIntangibleAssetsAndGoodwillExplanatory
430 Provisions Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForProvisionsExplanatory
431 Contingent liabilities, contingent assets and credit commitments Concept (Text Block (HTML)) For Period wbk:DescriptionOfAccountingPolicyForContingentLiabilitiesContingentAssetsAndCreditCommitmentsPolicyTextBlock
432 Shareholders' equity Concept (Text Block (HTML)) For Period wbk:DescriptionOfAccountingPolicyForShareholdersEquityPolicyTextBlock
433 Investments in subsidiaries and associates Concept (Text Block (HTML)) For Period wbk:DescriptionOfAccountingPolicyForInterestsInOtherEntitiesPolicyTextBlock
434 Structured entities Concept (Text Block (HTML)) For Period wbk:DescriptionOfAccountingPolicyForStructuredEntitiesPolicyTextBlock
435 Share-based payments Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForSharebasedPaymentTransactionsExplanatory
436 Superannuation commitments Concept (Text Block (HTML)) For Period wbk:DescriptionOfAccountingPolicyForSuperannuationCommitmentsPolicyTextBlock
437 Notes to the cash flow statements Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForCashFlowsExplanatory
438 30203 - Disclosure - Segment reporting (Tables) Network

*

*

 http://www.westpac.com.au/role/DisclosureSegmentReportingTables
439 Implied Table Table

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 implied:Table
440 Segment reporting Abstract ifrs-full:DisclosureOfOperatingSegmentsAbstract
441 Schedule of segment results on a cash earnings basis Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfOperatingSegmentsExplanatory
442 Schedule of reconciliation of cash earnings to net profit Concept (Text Block (HTML)) For Period wbk:DisclosureOfReconciliationOfCashEarningsToNetProfitExplanatoryTableTextBlock
443 Schedule of geographic segments Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfGeographicalAreasExplanatory
444 30303 - Disclosure - Net interest income (Tables) Network

*

*

 http://www.westpac.com.au/role/DisclosureNetInterestIncomeTables
445 Implied Table Table

*

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 implied:Table
446 Net interest income Abstract wbk:InterestIncomeAndExpensesAbstract
447 Schedule of interest income and expense Concept (Text Block (HTML)) For Period wbk:DisclosureOfInterestIncomeAndExpenseTableTextBlock
448 Schedule of interest income and expense related to financial instruments not measured at fair value through income statement Concept (Text Block (HTML)) For Period wbk:DisclosureOfInterestIncomeAndExpenseRelatedToFinancialInstrumentsNotMeasuredAtFairValueThroughIncomeStatementTableTextBlock
449 30403 - Disclosure - Non-interest income (Tables) Network

*

*

 http://www.westpac.com.au/role/DisclosureNonInterestIncomeTables
450 Implied Table Table

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 implied:Table
451 Non-interest income Abstract wbk:IfrsNonInterestIncomeAbstract
452 Schedule of non-interest income Concept (Text Block (HTML)) For Period wbk:DisclosureOfNonInterestIncomeTableTextBlock
453 30503 - Disclosure - Operating expenses (Tables) Network

*

*

 http://www.westpac.com.au/role/DisclosureOperatingExpensesTables
454 Implied Table Table

*

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 implied:Table
455 Operating expenses Abstract wbk:IfrsOperatingExpensesAbstract
456 Schedule of operating expenses Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfExpensesByNatureExplanatory
457 30603 - Disclosure - Impairment charges (Tables) Network

*

*

 http://www.westpac.com.au/role/DisclosureImpairmentChargesTables
458 Implied Table Table

*

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 implied:Table
459 Impairment charges Abstract ifrs-full:DisclosureOfImpairmentLossAndReversalOfImpairmentLossAbstract
460 Schedule of impairment charges Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfImpairmentLossAndReversalOfImpairmentLossExplanatory
461 30703 - Disclosure - Income tax (Tables) Network

*

*

 http://www.westpac.com.au/role/DisclosureIncomeTaxTables
462 Implied Table Table

*

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 implied:Table
463 Income tax Abstract ifrs-full:MajorComponentsOfTaxExpenseIncomeAbstract
464 Schedule of reconciliation to profit before income tax Concept (Text Block (HTML)) For Period wbk:IfrsScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock
465 Schedule of temporary differences attributable to deferred tax assets and deferred tax liabilities Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfTemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsExplanatory
466 Schedule of unrecognised deferred tax balances Concept (Text Block (HTML)) For Period wbk:DisclosureOfUnrecognisedDeferredTaxBalancesTableTextBlock
467 30803 - Disclosure - Earnings per share (Tables) Network

*

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 http://www.westpac.com.au/role/DisclosureEarningsPerShareTables
468 Implied Table Table

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 implied:Table
469 Earnings per share Abstract ifrs-full:EarningsPerShareAbstract
470 Schedule of earnings per share Concept (Text Block (HTML)) For Period ifrs-full:EarningsPerShareExplanatory
471 30903 - Disclosure - Average balance sheet and interest rates (Tables) Network

*

*

 http://www.westpac.com.au/role/DisclosureAverageBalanceSheetAndInterestRatesTables
472 Implied Table Table

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473 Average balance sheet and interest rates Abstract wbk:AverageBalanceSheetAndInterestRatesAbstract
474 Summary of the daily average balances of the Group's interest earning assets and interest bearing liabilities Concept (Text Block (HTML)) For Period wbk:AverageBalanceSheetAndInterestRatesTableTextBlock
475 Summary of change in net interest income Concept (Text Block (HTML)) For Period wbk:SummaryOfChangeInNetInterestIncomeTableTextBlock
476 31003 - Disclosure - Receivables due from other financial institutions (Tables) Network

*

*

 http://www.westpac.com.au/role/DisclosureReceivablesDueFromOtherFinancialInstitutionsTables
477 Implied Table Table

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 implied:Table
478 Receivables due from other financial institutions Abstract wbk:ReceivablesDueFromOtherFinancialInstitutionsAbstract
479 Summary of receivables due from other financial institutions Concept (Text Block (HTML)) For Period wbk:ReceivablesDueFromOtherFinancialInstitutionsTableTextBlock
480 31103 - Disclosure - Trading securities and financial assets designated at fair value (Tables) Network

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 http://www.westpac.com.au/role/DisclosureTradingSecuritiesAndFinancialAssetsDesignatedAtFairValueTables
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*

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 ifrs-full:DisclosureOfFinancialAssetsTable
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484 Trading securities and financial assets designated at fair value Member wbk:TradingSecuritiesAndFinancialAssetsDesignatedAtFairValueMember
485 Trading securities Member ifrs-full:TradingSecuritiesMember
486 Other financial assets designated at fair value Member wbk:OtherFinancialAssetsDesignatedAtFairValueMember
487 Financial assets LineItems ifrs-full:DisclosureOfFinancialAssetsLineItems
488 Schedule of financial assets Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfFinancialAssetsExplanatory
489 31203 - Disclosure - Available-for-sale securities (Tables) Network

*

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 http://www.westpac.com.au/role/DisclosureAvailableForSaleSecuritiesTables
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*

*

 ifrs-full:DisclosureOfFinancialAssetsTable
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493 Available-for-sale securities Member wbk:IfrsAvailableForSaleSecuritiesMember
494 Financial assets LineItems ifrs-full:DisclosureOfFinancialAssetsLineItems
495 Schedule of financial assets Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfFinancialAssetsExplanatory
496 Schedule of maturities of the available-for-sale securities and their weighted-average yield Concept (Text Block (HTML)) For Period wbk:ScheduleOfMaturitiesAndWeightedAverageYieldOfAvailableForSaleSecuritiesTableTextBlock
497 31303 - Disclosure - Loans (Tables) Network

*

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 http://www.westpac.com.au/role/DisclosureLoansTables
498 Disclosure of financial assets [table] Table

*

*

 ifrs-full:DisclosureOfFinancialAssetsTable
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501 Loans Member wbk:LoansAndFinanceLeasesReceivableMember
502 Finance lease receivables included in loans Member ifrs-full:LeaseReceivablesMember
503 Financial assets LineItems ifrs-full:DisclosureOfFinancialAssetsLineItems
504 Schedule of financial assets Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfFinancialAssetsExplanatory
505 Schedule of loans presented based on their industry classification Concept (Text Block (HTML)) For Period wbk:DisclosureOfLoansPresentedBasedOnTheirIndustryClassificationTableTextBlock
506 Schedule of consolidated contractual maturity distribution of all loans by type of customer Concept (Text Block (HTML)) For Period wbk:DisclosureOfConsolidatedContractualMaturityDistributionOfLoansByTypeOfCustomerTableTextBlock
507 Schedule of interest rate segmentation of loans maturing after one year Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfFinancialInstrumentsByTypeOfInterestRateExplanatory
508 31403 - Disclosure - Provisions for impairment charges (Tables) Network

*

*

 http://www.westpac.com.au/role/DisclosureProvisionsForImpairmentChargesTables
509 Implied Table Table

*

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 implied:Table
510 Provisions for impairment charges Abstract wbk:DisclosureOfProvisionsForImpairmentChargesAbstract
511 Schedule of changes in provisions for impairment charges on loans Concept (Text Block (HTML)) For Period wbk:ScheduleOfActivityInProvisionsForImpairmentChargesOnLoansTableTextBlock
512 Schedule of provisions for impairment charges on loans by industry classification Concept (Text Block (HTML)) For Period wbk:ScheduleOfProvisionsForImpairmentChargesOnLoansByIndustryClassificationTableTextBlock
513 Schedule of write-offs and recoveries of loans, by industry classification Concept (Text Block (HTML)) For Period wbk:DisclosureOfLoanWriteOffsAndRecoveriesByIndustryClassificationTableTextBlock
514 31503 - Disclosure - Life insurance assets and life insurance liabilities (Tables) Network

*

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 http://www.westpac.com.au/role/DisclosureLifeInsuranceAssetsAndLifeInsuranceLiabilitiesTables
515 Implied Table Table

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 implied:Table
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517 Schedule of life insurance assets and life insurance liabilities Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfAmountsArisingFromInsuranceContractsExplanatory
518 31603 - Disclosure - Payables due to other financial institutions (Tables) Network

*

*

 http://www.westpac.com.au/role/DisclosurePayablesDueToOtherFinancialInstitutionsTables
519 Implied Table Table

*

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 implied:Table
520 Payables due to other financial institutions Abstract ifrs-full:TradeAndOtherPayablesAbstract
521 Summary of payables due to other financial institutions Concept (Text Block (HTML)) For Period wbk:PayablesDueToOtherFinancialInstitutionsTableTextBlock
522 31703 - Disclosure - Deposits and other borrowings (Tables) Network

*

*

 http://www.westpac.com.au/role/DisclosureDepositsAndOtherBorrowingsTables
523 Implied Table Table

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 implied:Table
524 Deposits and other borrowings Abstract wbk:DisclosureOfDepositsAndOtherBorrowingsAbstract
525 Schedule of total deposits and other borrowings Concept (Text Block (HTML)) For Period wbk:DisclosureOfDetailedInformationAboutDepositsAndOtherBorrowingsTableTextBlock
526 Schedule of average balances and average rates for major categories of deposits Concept (Text Block (HTML)) For Period wbk:DisclosureOfAverageBalancesAndAverageRatesForMajorCategoriesOfDepositsTableTextBlock
527 Schedule of maturity profile of certificates of deposit and term deposits greater than US$100,000 Concept (Text Block (HTML)) For Period wbk:DisclosureOfMaturityProfileOfCertificatesOfDepositsAndTermDepositsMoreThanUs100000TableTextBlock
528 31803 - Disclosure - Other financial liabilities at fair value through income statement (Tables) Network

*

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 http://www.westpac.com.au/role/DisclosureOtherFinancialLiabilitiesAtFairValueThroughIncomeStatementTables
529 Implied Table Table

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530 Other financial liabilities at fair value through income statement Abstract ifrs-full:FinancialLiabilitiesAtFairValueThroughProfitOrLossAbstract
531 Schedule of other financial liabilities at fair value through income statement Concept (Text Block (HTML)) For Period wbk:ScheduleOfOtherFinancialLiabilitiesAtFairValueThroughProfitOrLossTableTextBlock
532 31903 - Disclosure - Debt issues (Tables) Network

*

*

 http://www.westpac.com.au/role/DisclosureDebtIssuesTables
533 Implied Table Table

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*

 implied:Table
534 Debt issues Abstract ifrs-full:BorrowingCostsAbstract
535 Schedule of distinction between short-term and long-term debt is based on the original maturity of the underlying security Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfDebtSecuritiesExplanatory
536 32003 - Disclosure - Loan Capital (Tables) Network

*

*

 http://www.westpac.com.au/role/DisclosureLoanCapitalTables
537 Disclosure of detailed information about borrowings [table] Table

*

*

 ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsTable
538 Borrowings by name [axis] Axis ifrs-full:BorrowingsByNameAxis
539 Borrowings by name [member] Member ifrs-full:BorrowingsByNameMember
540 Additional Tier 1 (AT1) loan capital Member wbk:AdditionalTierOneLoanCapitalMember
541 Tier 2 loan capital Member wbk:TierTwoLoanCapitalMember
542 Disclosure of detailed information about borrowings [line items] LineItems ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsLineItems
543 Schedule of loan capital Concept (Text Block (HTML)) For Period wbk:ScheduleOfLoanCapitalTableTextBlock
544 32103 - Disclosure - Derivative financial instruments (Tables) Network

*

*

 http://www.westpac.com.au/role/DisclosureDerivativeFinancialInstrumentsTables
545 Implied Table Table

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*

 implied:Table
546 Derivative financial instruments Abstract ifrs-full:DisclosureOfFinancialInstrumentsAbstract
547 Summary of fair value hedging of interest rate risk Concept (Text Block (HTML)) For Period wbk:DisclosureOfFairValueHedgingOfInterestRateRiskTableTextBlock
548 Schedule of cash flow hedge, cash inflows and outflows as a proportion to total gross cash flows and cash flow hedge ineffectiveness Concept (Text Block (HTML)) For Period wbk:DisclosureOfCashFlowHedgeCashInflowsAndOutflowsAsProportionToTotalGrossCashFlowsAndCashFlowHedgeIneffectivenessTableTextBlock
549 Summary of notional amount and fair value of derivative financial instruments held for trading and hedging Concept (Text Block (HTML)) For Period wbk:DisclosureOfNotionalAmountAndFairValueOfDerivativeFinancialInstrumentsHeldForTradingAndHedgingTableTextBlock
550 Summary of notional amount and fair value of Credit default swaps Concept (Text Block (HTML)) For Period wbk:DisclosureOfNotionalAmountAndFairValueOfCreditDefaultSwapsTableTextBlock
551 32203 - Disclosure - Financial risk (Tables) Network

*

*

 http://www.westpac.com.au/role/DisclosureFinancialRiskTables
552 Disclosure of detailed information about financial instruments [table] Table

*

*

 ifrs-full:DisclosureOfFinancialInstrumentsTable
553 Impairment of financial assets [axis] Axis ifrs-full:ImpairmentOfFinancialAssetsAxis
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555 Neither past due nor impaired Member ifrs-full:FinancialAssetsNeitherPastDueNorImpairedMember
556 Past due but not impaired Member ifrs-full:FinancialAssetsPastDueButNotImpairedMember
557 Impaired Member ifrs-full:FinancialAssetsImpairedMember
558 Fair values of financial assets and financial liabilities LineItems ifrs-full:DisclosureOfFinancialInstrumentsLineItems
559 Schedule of high level CRGs and corresponding external rating Concept (Text Block (HTML)) For Period wbk:DisclosureOfCreditRiskRatingsTableTextBlock
560 Schedule of credit risk exposure Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfCreditRiskExposureExplanatory
561 Schedule of credit quality of financial assets Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfProvisionMatrixExplanatory
562 Summary of financial assets past due but not impaired, disaggregated by days overdue Concept (Text Block (HTML)) For Period ifrs-full:AnalysisOfAgeOfFinancialAssetsThatArePastDueButNotImpaired
563 Summary of financial assets in default and not impaired Concept (Text Block (HTML)) For Period wbk:InformationAboutFinancialAssetsInDefaultButNotImpairedTableTextBlock
564 Schedule of gross amount of impaired loans and provision for impairment Concept (Text Block (HTML)) For Period wbk:DisclosureOfImpairedLoansAndProvisionForImpairmentExplanatoryTableTextBlock
565 Schedule of gross amount of impaired loans and provision for impairment by type and geography Concept (Text Block (HTML)) For Period wbk:DisclosureOfImpairedLoansAndProvisionForImpairmentByTypeAndGeographyExplanatoryTableTextBlock
566 Summary of interest received and forgone on non-performing loans and restructured financial assets Concept (Text Block (HTML)) For Period wbk:DisclosureOfInterestReceivedAndForgoneOnNonPerformingAssetsAndRestructuredFinancialAssetsExplanatoryTableTextBlock
567 Schedule of loan portfolio having coverage from collateral held Concept (Text Block (HTML)) For Period wbk:DisclosureOfCoverageOfLoanPortfolioToCollateralValueRatioExplanatoryTableTextBlock
568 Summary of collateral held against financial assets other than loans Concept (Text Block (HTML)) For Period wbk:DisclosureOfCollateralHeldAgainstFinancialAssetsOtherThanLoansExplanatoryTableTextBlock
569 Summary of the Group's liquid asset holdings Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfManagingLiquidityRisk
570 Summary of Group's funding composition Concept (Text Block (HTML)) For Period wbk:DisclosureOfFundingCompositionTableTextBlock
571 Schedule of Parent Entity's credit ratings Concept (Text Block (HTML)) For Period wbk:DisclosureOfParentEntityCreditRatingsTableTextBlock
572 Summary of financial assets pledged as collateral Concept (Text Block (HTML)) For Period wbk:DisclosureOfAssetsPledgedAsCollateralExplanatoryTableTextBlock
573 Schedule of contractual maturity of financial liabilities - derivative financial instruments Concept (Text Block (HTML)) For Period ifrs-full:MaturityAnalysisForDerivativeFinancialLiabilities
574 Schedule of contractual maturity of financial liabilities - other financial liabilities Concept (Text Block (HTML)) For Period ifrs-full:MaturityAnalysisForNonderivativeFinancialLiabilities
575 Schedule of expected maturity of assets and liabilities Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfAmountsToBeRecoveredOrSettledAfterTwelveMonthsForClassesOfAssetsAndLiabilitiesThatContainAmountsToBeRecoveredOrSettledBothNoMoreAndMoreThanTwelveMonthsAfterReportingDateExplanatory
576 Summary of aggregate VaR, by risk type Concept (Text Block (HTML)) For Period wbk:DisclosureOfTradedMarketRiskExplanatoryTableTextBlock
577 Summary of net interest income-at-risk (NaR) Concept (Text Block (HTML)) For Period wbk:DisclosureOfNetInterestIncomeAtRiskNonTradedMarketRiskExplanatoryTableTextBlock
578 Summary of Value at Risk - IRRBB Concept (Text Block (HTML)) For Period wbk:DisclosureOfInterestRateRiskInBankingBookNonTradedMarketRiskExplanatoryTableTextBlock
579 32303 - Disclosure - Fair values of financial assets and financial liabilities (Tables) Network

*

*

 http://www.westpac.com.au/role/DisclosureFairValuesOfFinancialAssetsAndFinancialLiabilitiesTables
580 Implied Table Table

*

*

 implied:Table
581 Fair values of financial assets and financial liabilities Abstract wbk:DisclosureOfFairValueMeasurementAbstract
582 Summary of financial instruments carried at fair value Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfFairValueOfFinancialInstrumentsExplanatory
583 Summary of changes in financial instruments measured at fair value derived from non-market observable valuation techniques Concept (Text Block (HTML)) For Period wbk:DisclosureOfSignificantUnobservableInputsUsedInFairValueMeasurementOfFinancialInstrumentsTableTextBlock
584 Schedule of financial instruments not measured at fair value Concept (Text Block (HTML)) For Period wbk:DisclosureOfFinancialInstrumentsNotMeasuredAtFairValueTableTextBlock
585 32403 - Disclosure - Offsetting financial assets and financial liabilities (Tables) Network

*

*

 http://www.westpac.com.au/role/DisclosureOffsettingFinancialAssetsAndFinancialLiabilitiesTables
586 Implied Table Table

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*

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587 Offsetting financial assets and financial liabilities Abstract wbk:DisclosureOfOffsettingOfFinancialAssetsAndFinancialLiabilitiesAbstract
588 Schedule of offsetting financial assets and financial liabilities Concept (Text Block (HTML)) For Period wbk:ScheduleOfOffsettingOfFinancialAssetsAndFinancialLiabilitiesTableTextBlock
589 32503 - Disclosure - Securitisation, covered bonds and other transferred assets (Tables) Network

*

*

 http://www.westpac.com.au/role/DisclosureSecuritisationCoveredBondsAndOtherTransferredAssetsTables
590 Implied Table Table

*

*

 implied:Table
591 Securitisation, covered bonds and other transferred assets Abstract ifrs-full:DisclosureOfFinancialAssetsTransferredDuringPeriodWhichDoNotQualifyForDerecognitionAbstract
592 Schedule of assets transferred and their associated liabilities Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfFinancialAssetsTransferredDuringPeriodWhichDoNotQualifyForDerecognitionExplanatory
593 32603 - Disclosure - Intangible assets (Tables) Network

*

*

 http://www.westpac.com.au/role/DisclosureIntangibleAssetsTables
594 Implied Table Table

*

*

 implied:Table
595 Intangible assets Abstract ifrs-full:IntangibleAssetsAndGoodwillAbstract
596 Schedule of changes in intangible assets and goodwill Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfReconciliationOfChangesInIntangibleAssetsAndGoodwillExplanatory
597 Schedule of allocation of goodwill Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfGoodwillExplanatory
598 32703 - Disclosure - Other assets (Tables) Network

*

*

 http://www.westpac.com.au/role/DisclosureOtherAssetsTables
599 Implied Table Table

*

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 implied:Table
600 Other assets Abstract ifrs-full:MiscellaneousAssetsAbstract
601 Schedule of other assets Concept (Text Block (HTML)) For Period wbk:DisclosureOfOtherAssetsTableTextBlock
602 32803 - Disclosure - Provisions (Tables) Network

*

*

 http://www.westpac.com.au/role/DisclosureProvisionsTables
603 Implied Table Table

*

*

 implied:Table
604 Provisions Abstract ifrs-full:ProvisionsAbstract
605 Schedule of changes in provisions Concept (Text Block (HTML)) For Period wbk:DisclosureOfReconciliationOfChangesInProvisionsTableTextBlock
606 32903 - Disclosure - Other liabilities (Tables) Network

*

*

 http://www.westpac.com.au/role/DisclosureOtherLiabilitiesTables
607 Implied Table Table

*

*

 implied:Table
608 Other liabilities Abstract ifrs-full:MiscellaneousLiabilitiesAbstract
609 Schedule of other liabilities Concept (Text Block (HTML)) For Period wbk:DisclosureOfOtherLiabilitiesTableTextBlock
610 33003 - Disclosure - Operating lease commitments (Tables) Network

*

*

 http://www.westpac.com.au/role/DisclosureOperatingLeaseCommitmentsTables
611 Implied Table Table

*

*

 implied:Table
612 Operating lease commitments Abstract wbk:OperatingLeaseCommitmentsAbstract
613 Schedule of operating lease commitments Concept (Text Block (HTML)) For Period wbk:DisclosureOfOperatingLeaseCommitmentsTableTextBlock
614 33103 - Disclosure - Contingent liabilities, contingent assets and credit commitments (Tables) Network

*

*

 http://www.westpac.com.au/role/DisclosureContingentLiabilitiesContingentAssetsAndCreditCommitmentsTables
615 Implied Table Table

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 implied:Table
616 Contingent liabilities, contingent assets and credit commitments Abstract ifrs-full:DisclosureOfContingentLiabilitiesAbstract
617 Schedule of undrawn credit commitments Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfCommitmentsExplanatory
618 Schedule of maturity of undrawn credit commitments Concept (Text Block (HTML)) For Period wbk:DisclosureOfMaturityOfCommitmentsTableTextBlock
619 33203 - Disclosure - Shareholders' equity (Tables) Network

*

*

 http://www.westpac.com.au/role/DisclosureShareholdersEquityTables
620 Implied Table Table

*

*

 implied:Table
621 Shareholders' equity Abstract ifrs-full:DisclosureOfClassesOfShareCapitalAbstract
622 Schedule of share capital Concept (Text Block (HTML)) For Period wbk:DisclosureOfShareCapitalTableTextBlock
623 Schedule of reconciliation of movement in number of ordinary shares Concept (Text Block (HTML)) For Period wbk:DisclosureOfReconciliationOfMovementInNumberOfOrdinarySharesTableTextBlock
624 Schedule of ordinary shares purchased on market Concept (Text Block (HTML)) For Period wbk:DisclosureOfOrdinarySharesPurchasedOnMarketTableTextBlock
625 Schedule of reconciliation of movement in reserves Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfReservesAndOtherEquityInterestExplanatory
626 33403 - Disclosure - Dividends (Tables) Network

*

*

 http://www.westpac.com.au/role/DisclosureDividendsTables
627 Implied Table Table

*

*

 implied:Table
628 Dividends Abstract wbk:DisclosureOfDividendsAbstract
629 Schedule of dividends not recognised at year end Concept (Text Block (HTML)) For Period wbk:ScheduleOfDividendsNotRecognisedAtYearEndTableTextBlock
630 33503 - Disclosure - Investments in subsidiaries and associates (Tables) Network

*

*

 http://www.westpac.com.au/role/DisclosureInvestmentsInSubsidiariesAndAssociatesTables
631 Disclosure of associates [table] Table

*

*

 ifrs-full:DisclosureOfSignificantInvestmentsInAssociatesTable
632 Associates [axis] Axis ifrs-full:SignificantInvestmentsInAssociatesAxis
633 Entity's total for associates [member] Member ifrs-full:EntitysTotalForAssociatesMember
634 Pendal Group Limited Member wbk:PendalGroupLimitedMember
635 Investments in subsidiaries and associates LineItems ifrs-full:DisclosureOfSignificantInvestmentsInAssociatesLineItems
636 Summary of ownership percentage of controlled entities Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfInterestsInSubsidiariesExplanatory
637 Schedule of interests in associates Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfInterestsInAssociatesExplanatory
638 33603 - Disclosure - Structured entities (Tables) Network

*

*

 http://www.westpac.com.au/role/DisclosureStructuredEntitiesTables
639 Implied Table Table

*

*

 implied:Table
640 Structured entities Abstract wbk:DisclosureOfInformationAboutStructuredEntitiesAbstract
641 Schedule of consolidated structured entities Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfInformationAboutConsolidatedStructuredEntitiesExplanatory
642 33703 - Disclosure - Share-based payments (Tables) Network

*

*

 http://www.westpac.com.au/role/DisclosureShareBasedPaymentsTables
643 Disclosure of terms and conditions of share-based payment arrangement [table] Table

*

*

 ifrs-full:DisclosureOfTermsAndConditionsOfSharebasedPaymentArrangementTable
644 Types of share-based payment arrangements [axis] Axis ifrs-full:TypesOfSharebasedPaymentArrangementsAxis
645 Share-based payment arrangements [member] Member ifrs-full:SharebasedPaymentArrangementsMember
646 Westpac Long Term Incentive Plan (LTIP) Member wbk:WestpacLongTermIncentivePlanMember
647 Westpac Performance Plan (WPP) Member wbk:WestpacPerformancePlanMember
648 Restricted Share Plan (RSP) Member wbk:RestrictedSharePlanMember
649 Employee Share Plan (ESP) Member wbk:EmployeeSharePlanMember
650 Share-based payments LineItems ifrs-full:DisclosureOfTermsAndConditionsOfSharebasedPaymentArrangementLineItems
651 Summary of terms and conditions of share-based payment arrangements Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfTermsAndConditionsOfSharebasedPaymentArrangementExplanatory
652 Schedule of share-based payment schemes Concept (Text Block (HTML)) For Period wbk:DisclosureOfSharebasedPaymentArrangementActivityTableTextBlock
653 33803 - Disclosure - Superannuation commitments (Tables) Network

*

*

 http://www.westpac.com.au/role/DisclosureSuperannuationCommitmentsTables
654 Implied Table Table

*

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 implied:Table
655 Superannuation commitments Abstract ifrs-full:DisclosureOfDefinedBenefitPlansAbstract
656 Schedule of contributions Concept (Text Block (HTML)) For Period wbk:DisclosureOfDefinedBenefitPlanContributionTableTextBlock
657 Summary of expenses recognised Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfInformationAboutMaturityProfileOfDefinedBenefitObligationExplanatory
658 Schedule of defined benefit balances recognised Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfNetDefinedBenefitLiabilityAssetExplanatory
659 Schedule of defined benefit plan significant assumptions Concept (Text Block (HTML)) For Period wbk:DisclosureOfDefinedBenefitPlanSignificantAssumptionsTableTextBlock
660 Summary of sensitivity analysis of essential assumptions Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfSensitivityAnalysisForActuarialAssumptionsExplanatory
661 Schedule of asset allocation Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfFairValueOfPlanAssetsExplanatory
662 33903 - Disclosure - Auditor's remuneration (Tables) Network

*

*

 http://www.westpac.com.au/role/DisclosureAuditorSRemunerationTables
663 Implied Table Table

*

*

 implied:Table
664 Auditor's remuneration Abstract ifrs-full:AuditorsRemunerationAbstract
665 Schedule of fees payable to auditor Concept (Text Block (HTML)) For Period wbk:DisclosureOfAuditorsRemunerationTableTextBlock
666 34003 - Disclosure - Related party disclosures (Tables) Network

*

*

 http://www.westpac.com.au/role/DisclosureRelatedPartyDisclosuresTables
667 Implied Table Table

*

*

 implied:Table
668 Related party disclosures Abstract ifrs-full:DisclosureOfTransactionsBetweenRelatedPartiesAbstract
669 Schedule of remuneration of KMP Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfInformationAboutKeyManagementPersonnelExplanatory
670 Schedule of loans provided and interest charged to KMP and their related parties Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfTransactionsBetweenRelatedPartiesExplanatory
671 Schedule of performance options and share rights held by key management personnel, including their related parties Concept (Text Block (HTML)) For Period wbk:ScheduleOfRelatedPartyPerformanceOptionsAndShareRightsTableTextBlock
672 34103 - Disclosure - Notes to the cash flow statements (Tables) Network

*

*

 http://www.westpac.com.au/role/DisclosureNotesToCashFlowStatementsTables
673 Implied Table Table

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674 Notes to the cash flow statements Abstract wbk:NotesToCashFlowStatementsAbstract
675 Summary of reconciliation of net cash provided by/(used in) operating activities to net profit Concept (Text Block (HTML)) For Period wbk:DisclosureOfReconciliationOfNetCashInOperatingActivitiesToNetProfitTableTextBlock
676 Summary of the assets and liabilities over which control ceased Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfNoncurrentAssetsOrDisposalGroupsClassifiedAsHeldForSaleExplanatory
677 Schedule of non-cash financing activities Concept (Text Block (HTML)) For Period wbk:ScheduleOfNonCashFinancingActivitiesTableTextBlock
678 40101 - Disclosure - Financial statements preparation (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureFinancialStatementsPreparationDetails
679 Disclosure of expected impact of initial application of new standards or interpretations [table] Table

*

*

 ifrs-full:DescriptionOfExpectedImpactOfInitialApplicationOfNewStandardsOrInterpretationsTable
680 New IFRSs [axis] Axis ifrs-full:NewIFRSsAxis
681 New IFRSs [member] Member ifrs-full:NewIFRSsMember
682 AASB 9 - Expected impact Member wbk:SB9FinancialInstrumentsMember
683 Disclosure of expected impact of initial application of new standards or interpretations [line items] LineItems ifrs-full:DescriptionOfExpectedImpactOfInitialApplicationOfNewStandardsOrInterpretationsLineItems
684 Retained earnings Concept (Monetary) As Of Credit ifrs-full:RetainedEarnings
685 Available-for-sale financial assets to reclassify to amortised cost Concept (Monetary) For Period Credit ifrs-full:ReclassificationOutOfAvailableforsaleFinancialAssets
686 40201 - Disclosure - Segment reporting - Segment results (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureSegmentReportingSegmentResultsDetails
687 Disclosure of operating segments [table] Table

*

*

 ifrs-full:DisclosureOfOperatingSegmentsTable
688 Segment consolidation items [axis] Axis ifrs-full:SegmentConsolidationItemsAxis
689 Entity's total for segment consolidation items [member] Member ifrs-full:EntitysTotalForSegmentConsolidationItemsMember
690 Operating segments (cash earnings) Member ifrs-full:OperatingSegmentsMember
691 Net cash earnings adjustment Member ifrs-full:MaterialReconcilingItemsMember
692 Segments [axis] Axis ifrs-full:SegmentsAxis
693 Segments [member] Member ifrs-full:SegmentsMember
694 Consumer Bank Member wbk:ConsumerBankMember
695 Business Bank Member wbk:BusinessBankMember
696 BT Financial Group (Australia) Member wbk:BtFinancialGroupAustraliaMember
697 Westpac Institutional Bank Member wbk:WestpacInstitutionalBankMember
698 Westpac New Zealand Member wbk:WestpacNewZealandMember
699 Group Businesses Member ifrs-full:AllOtherSegmentsMember
700 Segment reporting LineItems ifrs-full:DisclosureOfOperatingSegmentsLineItems
701 Maximum facility provided to customers Concept (Monetary) As Of Debit wbk:LoansAndAdvancesToCustomersMaximumFacilityAmount
702 Segment results on a cash earnings basis Abstract wbk:SegmentResultsOnCashEarningsBasisAbstract
703 Net interest income Concept (Monetary) For Period Credit ifrs-full:InterestRevenueExpense
704 Non-interest income Concept (Monetary) For Period Credit wbk:IfrsNoninterestIncome
705 Net operating income before operating expenses and impairment charges Concept (Monetary) For Period Credit wbk:NetOperatingIncomeBeforeOperatingExpenseAndImpairmentCharges
706 Operating expenses Concept (Monetary) For Period Debit ifrs-full:OperatingExpense
707 Impairment (charges)/benefits Concept (Monetary) For Period Debit ifrs-full:ImpairmentLossReversalOfImpairmentLossRecognisedInProfitOrLossLoansAndAdvances
708 Profit before income tax Concept (Monetary) For Period Credit ifrs-full:ProfitLossBeforeTax
709 Income tax expense Concept (Monetary) For Period Debit ifrs-full:IncomeTaxExpenseContinuingOperations
710 Net profit attributable to non-controlling interests Concept (Monetary) For Period Credit ifrs-full:ProfitLossAttributableToNoncontrollingInterests
711 Net profit attributable to owners of Westpac Banking Corporation Concept (Monetary) For Period Credit ifrs-full:ProfitLossAttributableToOwnersOfParent
712 Additional information Abstract ifrs-full:AdditionalInformationAbstract
713 Depreciation, amortisation and impairments Concept (Monetary) For Period Debit ifrs-full:DepreciationAmortisationAndImpairmentLossReversalOfImpairmentLossRecognisedInProfitOrLoss
714 Balance Sheet Abstract wbk:BalanceSheetAbstract
715 Total assets Concept (Monetary) As Of Debit ifrs-full:Assets
716 Total liabilities Concept (Monetary) As Of Credit ifrs-full:Liabilities
717 Additions of property and equipment and intangible assets Concept (Monetary) As Of Debit wbk:AdditionToPropertyPlantEquipmentAndIntangibleAssets
718 40202 - Disclosure - Segment reporting - Reconciliation of cash earnings to net profit (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureSegmentReportingReconciliationOfCashEarningsToNetProfitDetails
719 Disclosure of operating segments [table] Table

*

*

 ifrs-full:DisclosureOfOperatingSegmentsTable
720 Segment consolidation items [axis] Axis ifrs-full:SegmentConsolidationItemsAxis
721 Entity's total for segment consolidation items [member] Member ifrs-full:EntitysTotalForSegmentConsolidationItemsMember
722 Operating segments (cash earnings) Member ifrs-full:OperatingSegmentsMember
723 Net cash earnings adjustment Member ifrs-full:MaterialReconcilingItemsMember
724 Adjustments relating to Pendal (BTIM) Member wbk:MaterialReconcilingItemsAdjustmentsRelatingToPendalBtimMember
725 Amortisation of intangible assets Member wbk:MaterialReconcilingItemsAmortisationOfIntangibleAssetsMember
726 Acquisition, transaction and integration expenses Member wbk:MaterialReconcilingItemsAcquisitionTransactionAndIntegrationExpensesMember
727 Fair value gain/(loss) on economic hedges Member wbk:MaterialReconcilingItemsFairValueGainOrLossOnEconomicHedgesMember
728 Ineffective hedges Member wbk:MaterialReconcilingItemsIneffectiveHedgesMember
729 Treasury shares Member wbk:MaterialReconcilingItemsTreasurySharesMember
730 Segment reporting LineItems ifrs-full:DisclosureOfOperatingSegmentsLineItems
731 Net profit attributable to owners of Westpac Banking Corporation Concept (Monetary) For Period Credit ifrs-full:ProfitLossAttributableToOwnersOfParent
732 40203 - Disclosure - Segment reporting - Geographic segments (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureSegmentReportingGeographicSegmentsDetails
733 Disclosure of geographical areas [table] Table

*

*

 ifrs-full:DisclosureOfGeographicalAreasTable
734 Geographical areas [axis] Axis ifrs-full:GeographicalAreasAxis
735 Geographical areas [member] Member ifrs-full:GeographicalAreasMember
736 Australia Member ifrs-full:CountryOfDomicileMember
737 New Zealand Member country:NZ
738 Other Member wbk:PacificIslandsAsiaAmericasAndEuropeMember
739 Geographic segments LineItems ifrs-full:DisclosureOfGeographicalAreasLineItems
740 Revenue Concept (Monetary) For Period Credit ifrs-full:Revenue
741 Revenues (as a percent) Concept (Percent) For Period wbk:PercentageOfSegmentRevenues
742 Non-current assets Concept (Monetary) As Of Debit ifrs-full:NoncurrentAssetsOtherThanFinancialInstrumentsDeferredTaxAssetsPostemploymentBenefitAssetsAndRightsArisingUnderInsuranceContracts
743 Non-current assets (as a percent) Concept (Percent) As Of wbk:PercentageOfSegmentNonCurrentAssets
744 40301 - Disclosure - Net interest income (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureNetInterestIncomeDetails
745 Disclosure of detailed information about financial instruments [table] Table

*

*

 ifrs-full:DisclosureOfFinancialInstrumentsTable
746 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
747 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
748 Parent Entity Member us-gaap:ParentCompanyMember
749 Disclosure of detailed information about financial instruments [line items] LineItems ifrs-full:DisclosureOfFinancialInstrumentsLineItems
750 Interest income Abstract wbk:InterestIncomeAbstract
751 Cash and balances with central banks Concept (Monetary) For Period Credit ifrs-full:InterestIncomeOnCashAndBankBalancesAtCentralBanks
752 Receivables due from other financial institutions Concept (Monetary) For Period Credit wbk:InterestIncomeOnReceivablesDueFromOtherFinancialInstitutions
753 Net ineffectiveness on qualifying hedges Concept (Monetary) For Period Credit ifrs-full:GainLossOnHedgeIneffectivenessRecognisedInProfitOrLoss
754 Trading securities and financial assets designated at fair value Concept (Monetary) For Period Credit wbk:InterestIncomeOnTradingSecuritiesAndFinancialAssetsDesignatedAtFairValue
755 Available-for-sale securities Concept (Monetary) For Period Credit ifrs-full:InterestIncomeOnAvailableforsaleFinancialAssets
756 Loans Concept (Monetary) For Period Credit ifrs-full:InterestIncomeOnLoansAndReceivables
757 Regulatory deposits with central banks overseas Concept (Monetary) For Period Credit wbk:InterestIncomeOnMandatoryReserveDepositsAtCentralBanks
758 Due from subsidiaries Concept (Monetary) For Period Credit wbk:InterestIncomeOnAmountsDueFromSubsidiaries
759 Other interest income Concept (Monetary) For Period Credit ifrs-full:InterestIncomeOnOtherFinancialAssets
760 Total interest income Concept (Monetary) For Period Credit ifrs-full:RevenueFromInterest
761 Interest expense Abstract wbk:IfrsInterestExpenseAbstract
762 Payables due to other financial institutions Concept (Monetary) For Period Debit wbk:InterestExpenseOnPayablesDueToOtherFinancialInstitutions
763 Deposits and other borrowings Concept (Monetary) For Period Debit wbk:InterestExpenseOnDepositsAndOtherBorrowings
764 Trading liabilities Concept (Monetary) For Period Debit ifrs-full:InterestExpenseOnFinancialLiabilitiesHeldForTrading
765 Debt issues Concept (Monetary) For Period Debit ifrs-full:InterestExpenseOnDebtInstrumentsIssued
766 Due to subsidiaries Concept (Monetary) For Period Debit wbk:InterestExpenseOnAmountsDueToSubsidiaries
767 Loan capital Concept (Monetary) For Period Debit wbk:InterestExpenseOnLoanCapital
768 Bank levy Concept (Monetary) For Period Debit wbk:BankLevyExpense
769 Other interest expense Concept (Monetary) For Period Debit ifrs-full:InterestExpenseOnOtherFinancialLiabilities
770 Total interest expense Concept (Monetary) For Period Debit ifrs-full:InterestExpense
771 Net interest income Concept (Monetary) For Period Credit ifrs-full:InterestRevenueExpense
772 Amounts related to financial instruments not measured at fair value through income statement Abstract ifrs-full:InterestIncomeAndInterestExpenseForFinancialAssetsOrFinancialLiabilitiesNotAtFairValueThroughProfitOrLossAbstract
773 Interest income Concept (Monetary) For Period Credit ifrs-full:InterestIncomeForFinancialAssetsNotAtFairValueThroughProfitOrLoss
774 Interest expense Concept (Monetary) For Period Debit ifrs-full:InterestExpenseForFinancialLiabilitiesNotAtFairValueThroughProfitOrLoss
775 40401 - Disclosure - Non-interest income (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureNonInterestIncomeDetails
776 Disclosure of Income Statement Detail [Table] Table

*

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 wbk:DisclosureOfIncomeStatementDetailTable
777 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
778 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
779 Parent Entity Member us-gaap:ParentCompanyMember
780 Associates [axis] Axis ifrs-full:SignificantInvestmentsInAssociatesAxis
781 Entity's total for associates [member] Member ifrs-full:EntitysTotalForAssociatesMember
782 BTIM Member wbk:BtInvestmentManagementMember
783 Disclosure of Income Statement Detail [Line Items] LineItems wbk:DisclosureOfIncomeStatementDetailLineItems
784 Fee and commissions Abstract ifrs-full:FeeAndCommissionIncomeAbstract
785 Credit-related fee and commission income Concept (Monetary) For Period Credit ifrs-full:CreditrelatedFeeAndCommissionIncome
786 Transaction fees and commissions Concept (Monetary) For Period Credit ifrs-full:BrokerageFeeIncome
787 Other commissions earned Concept (Monetary) For Period Credit ifrs-full:OtherFeeAndCommissionIncome
788 Total fees and commissions Concept (Monetary) For Period Credit ifrs-full:FeeAndCommissionIncome
789 Wealth management and insurance income Abstract wbk:WealthManagementAndInsuranceIncomeAbstract
790 Life insurance and funds management net operating income Concept (Monetary) For Period Credit wbk:LifeInsuranceAndFundsManagementNetOperatingIncome
791 General insurance and lenders mortgage insurance net operating income Concept (Monetary) For Period Credit wbk:GeneralInsuranceAndLendersMortgageInsuranceNetOperatingIncome
792 Total wealth management and insurance income Concept (Monetary) For Period Credit wbk:WealthManagementAndInsuranceIncome
793 Trading income Concept (Monetary) For Period Credit ifrs-full:TradingIncomeExpense
794 Other income Abstract wbk:IfrsOtherIncomeAbstract
795 Dividends received from subsidiaries Concept (Monetary) For Period Credit wbk:DividendIncomeFromSubsidiaries
796 Dividends received from other entities Concept (Monetary) For Period Credit wbk:DividendIncomeFromOtherEntities
797 Net gain on sale of associates Concept (Monetary) For Period Credit wbk:GainLossOnDisposalOfInvestmentsInAssociates
798 Net gain on disposal of assets Concept (Monetary) For Period Credit ifrs-full:GainsLossesOnDisposalsOfPropertyPlantAndEquipment
799 Net gain/(loss) on hedging overseas operations Concept (Monetary) For Period Credit wbk:GainsLossesOnHedgesOfNetInvestmentsInForeignOperationsRecognisedInProfitOrLoss
800 Net gain/(loss) on derivatives held for risk management purposes Concept (Monetary) For Period Credit ifrs-full:GainsLossesOnChangeInFairValueOfDerivatives
801 Net gain/(loss) on financial instruments designated at fair value Concept (Monetary) For Period Credit wbk:GainsLossesOnFinancialInstrumentsAtFairValueThroughProfitOrLoss
802 Net gain/(loss) on disposal of controlled entities Concept (Monetary) For Period Credit ifrs-full:GainsLossesRecognisedWhenControlInSubsidiaryIsLost
803 Rental income on operating leases Concept (Monetary) For Period Credit ifrs-full:OperatingLeaseIncome
804 Share of associates' net profit/(loss) Concept (Monetary) For Period Credit ifrs-full:ShareOfProfitLossOfContinuingOperationsOfAssociatesAndJointVenturesAccountedForUsingEquityMethod
805 Other Concept (Monetary) For Period Credit ifrs-full:MiscellaneousOtherOperatingIncome
806 Total other income Concept (Monetary) For Period Credit ifrs-full:OtherIncome
807 Transactions with subsidiaries Concept (Monetary) For Period Credit wbk:IncomeFromTransactionsWithSubsidiaries
808 Total non-interest income Concept (Monetary) For Period Credit wbk:IfrsNoninterestIncome
809 Sale of shares in associate by the Group (in shares) Concept (Shares) For Period wbk:InvestmentInAssociatesSharesSold
810 Sale of shares in associate by the Group (as a percent) Concept (Percent) For Period wbk:ProportionOfOwnershipInterestInAssociateSold
811 40402 - Disclosure - Non-interest income - Wealth management and insurance income (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureNonInterestIncomeWealthManagementAndInsuranceIncomeDetails
812 Disclosure of Income Statement Detail [Table] Table

*

*

 wbk:DisclosureOfIncomeStatementDetailTable
813 Types of insurance contracts [axis] Axis ifrs-full:TypesOfInsuranceContractsAxis
814 Types of insurance contracts [member] Member ifrs-full:InsuranceContractsMember
815 Life insurance Member ifrs-full:LifeInsuranceContractsMember
816 General insurance and lenders mortgage insurance Member ifrs-full:NonlifeInsuranceContractsMember
817 Disclosure of Income Statement Detail [Line Items] LineItems wbk:DisclosureOfIncomeStatementDetailLineItems
818 Wealth management and insurance income comprised Abstract wbk:WealthManagementAndInsuranceIncomeAbstract
819 Funds management income Concept (Monetary) For Period Credit ifrs-full:PortfolioAndOtherManagementFeeIncome
820 Premium income/net premiums earned Concept (Monetary) For Period Credit ifrs-full:NetEarnedPremium
821 Commissions, investment income and other income Concept (Monetary) For Period Credit ifrs-full:IncomeArisingFromInsuranceContracts
822 Claims, changes in insurance liabilities, underwriting and commission expenses Concept (Monetary) For Period Debit ifrs-full:ExpenseArisingFromInsuranceContracts
823 Total wealth management and insurance income Concept (Monetary) For Period Credit wbk:WealthManagementAndInsuranceIncome
824 40501 - Disclosure - Operating expenses (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureOperatingExpensesDetails
825 Disclosure of Income Statement Detail [Table] Table

*

*

 wbk:DisclosureOfIncomeStatementDetailTable
826 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
827 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
828 Parent Entity Member us-gaap:ParentCompanyMember
829 Disclosure of Income Statement Detail [Line Items] LineItems wbk:DisclosureOfIncomeStatementDetailLineItems
830 Staff expenses Abstract ifrs-full:ClassesOfEmployeeBenefitsExpenseAbstract
831 Employee remuneration, entitlements and on-costs Concept (Monetary) For Period Debit ifrs-full:ShorttermEmployeeBenefitsExpense
832 Superannuation expense Concept (Monetary) For Period Debit wbk:PostEmploymentBenefitExpense
833 Share-based payments Concept (Monetary) For Period Debit ifrs-full:ExpenseFromSharebasedPaymentTransactionsWithEmployees
834 Restructuring costs Concept (Monetary) For Period Debit ifrs-full:ExpenseOfRestructuringActivities
835 Total staff expenses Concept (Monetary) For Period Debit ifrs-full:EmployeeBenefitsExpense
836 Occupancy expenses Abstract wbk:OccupancyExpensesAbstract
837 Operating lease rentals Concept (Monetary) For Period Debit ifrs-full:LeaseAndSubleasePaymentsRecognisedAsExpense
838 Depreciation of property and equipment Concept (Monetary) For Period ifrs-full:DepreciationPropertyPlantAndEquipment
839 Other Concept (Monetary) For Period Debit wbk:OccupancyExpensesOther
840 Total occupancy expenses Concept (Monetary) For Period Debit ifrs-full:OccupancyExpense
841 Technology expenses Abstract wbk:TechnologyExpensesAbstract
842 Amortisation and impairment of software assets Concept (Monetary) For Period Debit wbk:AmortisationAndImpairmentOfSoftwareAssets
843 Depreciation and impairment of IT equipment Concept (Monetary) For Period Debit wbk:AmortisationAndImpairmentOfInformationTechnologyEquipment
844 Technology services Concept (Monetary) For Period Debit wbk:TechnologyServicesExpense
845 Software maintenance and licences Concept (Monetary) For Period Debit wbk:SoftwareMaintenanceAndLicencesExpense
846 Telecommunications Concept (Monetary) For Period Debit ifrs-full:CommunicationExpense
847 Data processing Concept (Monetary) For Period Debit wbk:DataProcessingExpense
848 Total technology expenses Concept (Monetary) For Period Debit wbk:TechnologyExpenses
849 Other expenses Abstract ifrs-full:ExpenseByNatureAbstract
850 Professional and processing services Concept (Monetary) For Period Debit wbk:ProfessionalAndProcessingServicesExpense
851 Amortisation and impairment of intangible assets and deferred expenditure Concept (Monetary) For Period Debit wbk:AmortisationAndImpairmentOfIntangibleAssetsAndDeferredExpenditure
852 Postage and stationery Concept (Monetary) For Period Debit wbk:PostageAndStationeryExpense
853 Advertising Concept (Monetary) For Period Debit ifrs-full:AdvertisingExpense
854 Credit card loyalty programs Concept (Monetary) For Period Debit wbk:CreditCardLoyaltyProgramExpense
855 Non-lending losses Concept (Monetary) For Period Debit wbk:AdditionalAllowanceRecognisedInProfitOrLossAllowanceAccountForCreditLossesOfFinancialAssetsOtherThanLoansAndAdvances
856 Impairment/(reversal of impairment) on investments in subsidiaries Concept (Monetary) For Period Debit wbk:ImpairmentLossReversalOfImpairmentLossRecognisedInProfitOrLossInvestmentsInSubsidiaries
857 Other expenses Concept (Monetary) For Period Debit ifrs-full:MiscellaneousOtherOperatingExpense
858 Total other expenses Concept (Monetary) For Period Debit ifrs-full:OtherExpenseByNature
859 Total operating expenses Concept (Monetary) For Period Debit ifrs-full:OperatingExpense
860 Professional and processing services Abstract wbk:ProfessionalAndProcessingServicesAbstract
861 Services provided by external suppliers Concept (Monetary) For Period Debit wbk:ProfessionalAndProcessingServicesExpenseMiscellaneous
862 Operations processing Concept (Monetary) For Period Debit wbk:ProfessionalAndProcessingServicesOperationsProcessingExpense
863 Consultants Concept (Monetary) For Period Debit wbk:ProfessionalAndProcessingServicesConsultingFees
864 Credit assessment Concept (Monetary) For Period Debit wbk:ProfessionalAndProcessingServicesCreditAssessmentExpense
865 Legal and audit fees Concept (Monetary) For Period Debit wbk:ProfessionalAndProcessingServicesLegalAndAuditFees
866 Regulatory fees and share market related costs Concept (Monetary) For Period Debit wbk:ProfessionalAndProcessingServicesRegulatoryFeesAndShareMarketRelatedCosts
867 40601 - Disclosure - Impairment charges (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureImpairmentChargesDetails
868 Disclosure of impairment loss and reversal of impairment loss [table] Table

*

*

 ifrs-full:DisclosureOfImpairmentLossAndReversalOfImpairmentLossTable
869 Method of assessment of expected credit losses [axis] Axis ifrs-full:MethodOfAssessmentOfExpectedCreditLossesAxis
870 Method of assessment of expected credit losses [member] Member ifrs-full:MethodOfAssessmentOfExpectedCreditLossesMember
871 Individually assessed Member ifrs-full:ExpectedCreditLossesIndividuallyAssessedMember
872 Collectively assessed Member ifrs-full:ExpectedCreditLossesCollectivelyAssessedMember
873 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
874 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
875 Parent Entity Member us-gaap:ParentCompanyMember
876 Impairment charges LineItems ifrs-full:DisclosureOfImpairmentLossAndReversalOfImpairmentLossLineItems
877 Provisions raised Concept (Monetary) For Period ifrs-full:ImpairmentLossRecognisedInProfitOrLossLoansAndAdvances
878 Write-backs Concept (Monetary) For Period ifrs-full:ReversalOfImpairmentLossRecognisedInProfitOrLossLoansAndAdvances
879 Recoveries Concept (Monetary) For Period Credit ifrs-full:GainOnRecoveryOfLoansAndAdvancesPreviouslyWrittenOff
880 Impairment charges Concept (Monetary) For Period Debit ifrs-full:ImpairmentLossReversalOfImpairmentLossRecognisedInProfitOrLossLoansAndAdvances
881 40701 - Disclosure - Income tax - Reconciliation to profit before income tax (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureIncomeTaxReconciliationToProfitBeforeIncomeTaxDetails
882 Disclosure of geographical areas [table] Table

*

*

 ifrs-full:DisclosureOfGeographicalAreasTable
883 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
884 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
885 Parent Entity Member us-gaap:ParentCompanyMember
886 Geographical areas [axis] Axis ifrs-full:GeographicalAreasAxis
887 Geographical areas [member] Member ifrs-full:GeographicalAreasMember
888 Australia Member ifrs-full:CountryOfDomicileMember
889 Overseas Member ifrs-full:ForeignCountriesMember
890 Income tax LineItems wbk:IncomeTaxDisclosureLineItems
891 Profit before taxes Concept (Monetary) For Period Credit ifrs-full:AccountingProfit
892 Tax at the Australian company tax rate of 30% Concept (Monetary) For Period Debit ifrs-full:TaxExpenseIncomeAtApplicableTaxRate
893 Australian company tax rate Concept (Percent) For Period ifrs-full:ApplicableTaxRate
894 Hybrid capital distributions Concept (Monetary) For Period Debit wbk:TaxEffectOfHybridCapitalDistributions
895 Tax adjustment on policyholder earnings Concept (Monetary) For Period Debit wbk:TaxEffectOfTaxAdjustmentOnPolicyholderEarnings
896 Adjustment for life business tax rates Concept (Monetary) For Period Debit wbk:TaxEffectOfAdjustmentForLifeBusinessTaxRates
897 Dividend adjustments Concept (Monetary) For Period Credit wbk:TaxEffectOfDividendAdjustments
898 Other non-assessable items Concept (Monetary) For Period Credit ifrs-full:TaxEffectOfRevenuesExemptFromTaxation2011
899 Other non-deductible items Concept (Monetary) For Period Debit ifrs-full:TaxEffectOfExpenseNotDeductibleInDeterminingTaxableProfitTaxLoss
900 Adjustment for overseas tax rates Concept (Monetary) For Period Debit ifrs-full:TaxEffectOfForeignTaxRates
901 Other items Concept (Monetary) For Period Debit ifrs-full:OtherTaxEffectsForReconciliationBetweenAccountingProfitAndTaxExpenseIncome
902 Total income tax expense Concept (Monetary) For Period Debit ifrs-full:IncomeTaxExpenseContinuingOperations
903 Current income tax Concept (Monetary) For Period Debit ifrs-full:CurrentTaxExpenseIncomeAndAdjustmentsForCurrentTaxOfPriorPeriods
904 Movement in deferred tax Concept (Monetary) For Period Debit ifrs-full:DeferredTaxExpenseIncome
905 Income tax (over)/under provided in prior years Concept (Monetary) For Period Debit wbk:AdjustmentsForCurrentAndDeferredTaxOfPriorPeriods
906 Effective tax rate Concept (Percent) For Period ifrs-full:AverageEffectiveTaxRate
907 40702 - Disclosure - Income tax - Deferred tax assets (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureIncomeTaxDeferredTaxAssetsDetails
908 Disclosure of temporary difference, unused tax losses and unused tax credits [table] Table

*

*

 ifrs-full:DisclosureOfTemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsTable
909 Temporary difference, unused tax losses and unused tax credits [axis] Axis ifrs-full:TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsAxis
910 Temporary difference, unused tax losses and unused tax credits [member] Member ifrs-full:TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsMember
911 Provision for impairment charges on loans Member ifrs-full:AllowanceForCreditLossesMember
912 Provision for long service leave, annual leave and other employee benefits Member wbk:ProvisionForEmployeeBenefitsMember
913 Financial instruments Member wbk:FinancialInstrumentsMember
914 Property and equipment Member ifrs-full:PropertyPlantAndEquipmentMember
915 Other provisions Member ifrs-full:OtherProvisionsMember
916 Other liabilities Member wbk:IfrsOtherLiabilitiesMember
917 Cashflow hedges Member ifrs-full:ReserveOfCashFlowHedgesMember
918 Defined benefit Member ifrs-full:ReserveOfRemeasurementsOfDefinedBenefitPlansMember
919 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
920 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
921 Parent Entity Member us-gaap:ParentCompanyMember
922 Deferred tax assets LineItems ifrs-full:DisclosureOfTemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsLineItems
923 Gross deferred tax assets recognised in the income statements Concept (Monetary) As Of Debit wbk:GrossDeferredTaxAssetsRecognisedInIncomeStatement
924 Gross deferred tax assets recognised directly in other comprehensive income Concept (Monetary) As Of Debit wbk:GrossDeferredTaxAssetsRecognisedInOtherComprehensiveIncome
925 Deferred tax assets Concept (Monetary) As Of Debit ifrs-full:DeferredTaxAssets
926 Set-off of deferred tax assets and deferred tax liabilities Concept (Monetary) As Of wbk:SetoffOfDeferredTaxAssetsAndDeferredTaxLiabilities
927 Net deferred tax assets Concept (Monetary) As Of Debit ifrs-full:NetDeferredTaxAssets
928 40703 - Disclosure - Income tax - Movements in deferred tax assets (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureIncomeTaxMovementsInDeferredTaxAssetsDetails
929 Disclosure of temporary difference, unused tax losses and unused tax credits [table] Table

*

*

 ifrs-full:DisclosureOfTemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsTable
930 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
931 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
932 Parent Entity Member us-gaap:ParentCompanyMember
933 Disclosure of temporary difference, unused tax losses and unused tax credits [line items] LineItems ifrs-full:DisclosureOfTemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsLineItems
934 Movements Abstract wbk:ReconciliationOfChangesInDeferredTaxAssetAbstract
935 Opening balance Concept (Monetary) As Of Debit ifrs-full:NetDeferredTaxAssets
936 Recognised in the income statements Concept (Monetary) For Period wbk:DeferredTaxExpenseIncomeRecognisedInProfitOrLossDeferredTaxAssets
937 Recognised in other comprehensive income Concept (Monetary) For Period wbk:DeferredTaxExpenseIncomeRecognisedInOtherComprehensiveIncomeDeferredTaxAssets
938 Set-off of deferred tax assets and deferred tax liabilities Concept (Monetary) For Period wbk:DeferredTaxExpenseIncomeSetOffOfDeferredTaxAssetsAndLiabilities
939 Closing balance Concept (Monetary) As Of Debit ifrs-full:NetDeferredTaxAssets
940 40704 - Disclosure - Income tax - Deferred tax liabilities (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureIncomeTaxDeferredTaxLiabilitiesDetails
941 Disclosure of temporary difference, unused tax losses and unused tax credits [table] Table

*

*

 ifrs-full:DisclosureOfTemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsTable
942 Temporary difference, unused tax losses and unused tax credits [axis] Axis ifrs-full:TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsAxis
943 Temporary difference, unused tax losses and unused tax credits [member] Member ifrs-full:TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsMember
944 Financial instruments Member wbk:FinancialInstrumentsMember
945 Finance lease transactions Member wbk:FinanceLeaseTransactionMember
946 Property and equipment Member ifrs-full:PropertyPlantAndEquipmentMember
947 Life insurance assets Member wbk:LifeInsuranceAssetsMember
948 Other assets Member ifrs-full:OtherAssetsMember
949 Available-for-sale securities Member ifrs-full:ReserveOfGainsAndLossesOnRemeasuringAvailableforsaleFinancialAssetsMember
950 Defined benefit Member ifrs-full:ReserveOfRemeasurementsOfDefinedBenefitPlansMember
951 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
952 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
953 Parent Entity Member us-gaap:ParentCompanyMember
954 Deferred tax liabilities LineItems ifrs-full:DisclosureOfTemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsLineItems
955 Gross deferred tax liabilities recognised in the income statements Concept (Monetary) As Of Credit wbk:GrossDeferredTaxLiabilitiesRecognisedInIncomeStatement
956 Gross deferred tax liabilities recognised directly in other comprehensive income Concept (Monetary) As Of Credit wbk:GrossDeferredTaxLiabilitiesRecognisedInOtherComprehensiveIncome
957 Deferred tax liabilities Concept (Monetary) As Of Credit ifrs-full:DeferredTaxLiabilities
958 Set-off of deferred tax assets and deferred tax liabilities Concept (Monetary) As Of wbk:SetoffOfDeferredTaxAssetsAndDeferredTaxLiabilities
959 Net deferred tax liabilities Concept (Monetary) As Of Credit ifrs-full:NetDeferredTaxLiabilities
960 40705 - Disclosure - Income tax - Movements in deferred tax liabilities (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureIncomeTaxMovementsInDeferredTaxLiabilitiesDetails
961 Disclosure of temporary difference, unused tax losses and unused tax credits [table] Table

*

*

 ifrs-full:DisclosureOfTemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsTable
962 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
963 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
964 Parent Entity Member us-gaap:ParentCompanyMember
965 Disclosure of temporary difference, unused tax losses and unused tax credits [line items] LineItems ifrs-full:DisclosureOfTemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsLineItems
966 Movements Abstract wbk:ReconciliationOfChangesInDeferredTaxLiabilityAbstract
967 Opening balance Concept (Monetary) As Of Credit ifrs-full:NetDeferredTaxLiabilities
968 Recognised in the income statements Concept (Monetary) For Period wbk:DeferredTaxExpenseIncomeRecognisedInProfitOrLossDeferredTaxLiabilities
969 Recognised in other comprehensive income Concept (Monetary) For Period wbk:DeferredTaxExpenseIncomeRecognisedInOtherComprehensiveIncomeDeferredTaxLiabilities
970 Set-off of deferred tax assets and deferred tax liabilities Concept (Monetary) For Period wbk:DeferredTaxExpenseIncomeSetOffOfDeferredTaxAssetsAndLiabilities
971 Closing balance Concept (Monetary) As Of Credit ifrs-full:NetDeferredTaxLiabilities
972 40706 - Disclosure - Income tax - Unrecognised deferred tax balances (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureIncomeTaxUnrecognisedDeferredTaxBalancesDetails
973 Income Tax Disclosure [Table] Table

*

*

 wbk:IncomeTaxDisclosureTable
974 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
975 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
976 Parent Entity Member us-gaap:ParentCompanyMember
977 Income tax LineItems wbk:IncomeTaxDisclosureLineItems
978 Australian company tax rate Concept (Percent) For Period ifrs-full:ApplicableTaxRate
979 Unrecognised deferred tax balances Abstract wbk:UnrecognisedDeferredTaxBalancesAbstract
980 Unrecognised deferred tax asset: Tax losses on revenue account Concept (Monetary) As Of ifrs-full:UnusedTaxLossesForWhichNoDeferredTaxAssetRecognised
981 Unrecognised deferred tax liability: Gross retained earnings of subsidiaries which the Parent Entity does not intend to distribute in the foreseeable future Concept (Monetary) As Of ifrs-full:TemporaryDifferencesAssociatedWithInvestmentsInSubsidiariesBranchesAndAssociatesAndInterestsInJointVentures
982 40801 - Disclosure - Earnings per share (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureEarningsPerShareDetails
983 Implied Table Table

*

*

 implied:Table
984 Earnings per share Abstract ifrs-full:EarningsPerShareAbstract
985 Net profit attributable to shareholders Concept (Monetary) For Period Credit ifrs-full:ProfitLossAttributableToOwnersOfParent
986 Adjustment for Restricted Share Plan (RSP) dividends Concept (Monetary) For Period Debit wbk:AdjustmentToProfitLossForRestrictedSharePlanDividends
987 Adjustment for potential dilution: Distributions to convertible loan capital holders Concept (Monetary) For Period Credit wbk:AdjustmentToProfitLossForDilutiveEffectOfConvertibleInstruments
988 Adjusted net profit attributable to shareholders - Basic Concept (Monetary) For Period Credit ifrs-full:ProfitLossAttributableToOrdinaryEquityHoldersOfParentEntity
989 Adjusted net profit attributable to shareholders - Diluted Concept (Monetary) For Period Credit ifrs-full:ProfitLossAttributableToOrdinaryEquityHoldersOfParentEntityIncludingDilutiveEffects
990 Weighted average number of ordinary shares on issue Concept (Shares) For Period wbk:WeightedAverageSharesIssued
991 Treasury shares (including RSP share rights) Concept (Shares) For Period wbk:WeighedAverageTreasuryShares
992 Adjustment for potential dilution: Share-based payments Concept (Shares) For Period ifrs-full:DilutiveEffectOfShareOptionsOnNumberOfOrdinaryShares
993 Adjustment for potential dilution: Convertible loan capital Concept (Shares) For Period ifrs-full:DilutiveEffectOfConvertibleInstrumentsOnNumberOfOrdinaryShares
994 Adjusted weighted average number of ordinary shares - Basic Concept (Shares) For Period ifrs-full:WeightedAverageShares
995 Adjusted weighted average number of ordinary shares - Diluted Concept (Shares) For Period ifrs-full:AdjustedWeightedAverageShares
996 Earnings per ordinary share - Basic (in dollars per share) Concept (Share) For Period ifrs-full:BasicEarningsLossPerShare
997 Earnings per ordinary share - Diluted (in dollars per share) Concept (Share) For Period ifrs-full:DilutedEarningsLossPerShare
998 40901 - Disclosure - Average balance sheet and interest rates (Details) Network

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*

 http://www.westpac.com.au/role/DisclosureAverageBalanceSheetAndInterestRatesDetails
999 Average Balance Sheet And Interest Rates [Table] Table

*

*

 wbk:AverageBalanceSheetAndInterestRatesTable
1000 Classes of assets [axis] Axis ifrs-full:ClassesOfAssetsAxis
1001 Assets [member] Member ifrs-full:ClassesOfAssetsMember
1002 Receivables due from other financial institutions Member wbk:ReceivablesDueFromOtherFinancialInstitutionsMember
1003 Trading securities and financial assets designated at fair value Member wbk:TradingSecuritiesAndFinancialAssetsDesignatedAtFairValueMember
1004 Available-for-sale securities Member wbk:IfrsAvailableForSaleSecuritiesMember
1005 Regulatory deposits with central banks overseas Member wbk:MandatoryReserveDepositsAtCentralBanksMember
1006 Loans and other receivables Member wbk:LoansAndOtherReceivablesMember
1007 Cash, receivables due from other financial institutions and regulatory deposits Member wbk:CashReceivablesDueFromOtherFinancialInstitutionsAndRegulatoryDepositsMember
1008 Derivative financial instruments Member wbk:DerivativeFinancialAssetsMember
1009 Life insurance assets Member wbk:LifeInsuranceAssetsMember
1010 Other assets Member ifrs-full:OtherAssetsMember
1011 Classes of liabilities [axis] Axis ifrs-full:ClassesOfLiabilitiesAxis
1012 Liabilities [member] Member ifrs-full:LiabilitiesMember
1013 Payables due to other financial institutions Member wbk:PayablesDueToOtherFinancialInstitutionsMember
1014 Deposits and other borrowings Member wbk:DepositsAndOtherBorrowingsMember
1015 Loan capital Member wbk:LoanCapitalMember
1016 Other interest bearing liabilities Member wbk:OtherInterestBearingLiabilitiesMember
1017 Deposits and payables due to other financial institutions Member wbk:DepositsAndPayablesDueToOtherFinancialInstitutionsMember
1018 Derivative financial instruments Member wbk:DerivativeFinancialLiabilitiesMember
1019 Life insurance liabilities Member wbk:LifeInsuranceLiabilitiesMember
1020 Other liabilities Member wbk:IfrsOtherLiabilitiesMember
1021 Geographical [Axis] Axis us-gaap:StatementGeographicalAxis
1022 Geographical [Domain] Member us-gaap:SegmentGeographicalDomain
1023 Australia Member country:AU
1024 New Zealand Member country:NZ
1025 Other Overseas Member wbk:OtherOverseasMember
1026 Average balance sheet and interest rates Abstract wbk:AverageBalanceSheetAndInterestRatesLineitems
1027 Average Balance - Interest earning assets Concept (Monetary) For Period Debit wbk:AverageBalanceOfInterestEarningAssets
1028 Interest Income Concept (Monetary) For Period Credit ifrs-full:RevenueFromInterest
1029 Average Rate - Interest earning assets (as a percent) Concept (Percent) For Period wbk:AverageRateOnInterestEarningAssets
1030 Average Balance - Non-Interest earning assets Concept (Monetary) For Period Debit wbk:AverageBalanceOfNonInterestEarningAssets
1031 Average Balance - Total assets Concept (Monetary) For Period Debit wbk:AverageBalanceOfTotalAssets
1032 Average Balance - Interest bearing liabilities Concept (Monetary) For Period Credit wbk:AverageBalanceOfInterestBearingLiabilities
1033 Interest Expense Concept (Monetary) For Period Debit ifrs-full:InterestExpense
1034 Average Rate - Interest bearing liabilities (as a percent) Concept (Percent) For Period wbk:AverageRateOnInterestBearingLiabilities
1035 Average Balance - Non-interest bearing liabilities Concept (Monetary) For Period Credit wbk:AverageBalanceOfNonInterestBearingLiabilities
1036 Average Balance - Total liabilities Concept (Monetary) For Period Credit wbk:AverageBalanceOfTotalLiabilities
1037 Average Balance - Shareholders' equity Concept (Monetary) For Period Credit wbk:AverageBalanceOfShareholdersEquity
1038 Average Balance - Non-controlling interests Concept (Monetary) For Period Credit wbk:AverageBalanceOfNonControllingInterests
1039 Average Balance - Total equity Concept (Monetary) For Period Credit wbk:AverageBalanceOfTotalEquity
1040 Average Balance - Total liabilities and equity Concept (Monetary) For Period Credit wbk:AverageBalanceOfTotalLiabilitiesAndEquity
1041 40902 - Disclosure - Average balance sheet and interest rates - Variances (Details) Network

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*

 http://www.westpac.com.au/role/DisclosureAverageBalanceSheetAndInterestRatesVariancesDetails
1042 Average Balance Sheet And Interest Rates [Table] Table

*

*

 wbk:AverageBalanceSheetAndInterestRatesTable
1043 Classes of assets [axis] Axis ifrs-full:ClassesOfAssetsAxis
1044 Assets [member] Member ifrs-full:ClassesOfAssetsMember
1045 Receivables due from other financial institutions Member wbk:ReceivablesDueFromOtherFinancialInstitutionsMember
1046 Trading securities and financial assets designated at fair value Member wbk:TradingSecuritiesAndFinancialAssetsDesignatedAtFairValueMember
1047 Available-for-sale securities Member wbk:IfrsAvailableForSaleSecuritiesMember
1048 Regulatory deposits with central banks overseas Member wbk:MandatoryReserveDepositsAtCentralBanksMember
1049 Loans and other receivables Member wbk:LoansAndOtherReceivablesMember
1050 Classes of liabilities [axis] Axis ifrs-full:ClassesOfLiabilitiesAxis
1051 Liabilities [member] Member ifrs-full:LiabilitiesMember
1052 Payables due to other financial institutions Member wbk:PayablesDueToOtherFinancialInstitutionsMember
1053 Deposits and other borrowings Member wbk:DepositsAndOtherBorrowingsMember
1054 Loan capital Member wbk:LoanCapitalMember
1055 Other interest bearing liabilities Member wbk:OtherInterestBearingLiabilitiesMember
1056 Geographical [Axis] Axis us-gaap:StatementGeographicalAxis
1057 Geographical [Domain] Member us-gaap:SegmentGeographicalDomain
1058 Australia Member country:AU
1059 New Zealand Member country:NZ
1060 Other Overseas Member wbk:OtherOverseasMember
1061 Average balance sheet and interest rates Abstract wbk:AverageBalanceSheetAndInterestRatesLineitems
1062 Interest income - Change Due to Volume Concept (Monetary) For Period Credit wbk:ChangeInInterestIncomeDueToVolume
1063 Interest income - Change Due to Rate Concept (Monetary) For Period Credit wbk:ChangeInInterestIncomeDueToInterestRates
1064 Total change in interest income Concept (Monetary) For Period Credit wbk:ChangeInInterestIncome
1065 Interest expense - Change Due to Volume Concept (Monetary) For Period Debit wbk:ChangeInInterestExpenseDueToVolume
1066 Interest expense - Change Due to Rate Concept (Monetary) For Period Debit wbk:ChangeInInterestExpensesDueToInterestRates
1067 Total change in interest expense Concept (Monetary) For Period Debit wbk:ChangeInInterestExpense
1068 Net interest income - Change Due to Volume Concept (Monetary) For Period Credit wbk:ChangeInNetInterestIncomeDueToVolume
1069 Net interest income - Change Due to Rate Concept (Monetary) For Period Credit wbk:ChangeInNetInterestIncomeDueToInterestRates
1070 Total change in net interest income Concept (Monetary) For Period Credit wbk:ChangeInNetInterestIncome
1071 41001 - Disclosure - Receivables due from other financial institutions (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureReceivablesDueFromOtherFinancialInstitutionsDetails
1072 Receivables Due From Other Financial Institutions [Table] Table

*

*

 wbk:ReceivablesDueFromOtherFinancialInstitutionsTable
1073 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
1074 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
1075 Parent Entity Member us-gaap:ParentCompanyMember
1076 Receivables due from other financial institutions LineItems wbk:ReceivablesDueFromOtherFinancialInstitutionsLineItems
1077 Conduit assets Concept (Monetary) As Of Debit wbk:ConduitAssets
1078 Cash collateral Concept (Monetary) As Of Debit wbk:CashCollateralDueFromOtherFinancialInstitutions
1079 Interbank lending Concept (Monetary) As Of Debit wbk:InterbankLending
1080 Total receivables due from other financial institutions Concept (Monetary) As Of Debit wbk:ReceivablesDueFromOtherFinancialInstitutions
1081 41101 - Disclosure - Trading securities and financial assets designated at fair value (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureTradingSecuritiesAndFinancialAssetsDesignatedAtFairValueDetails
1082 Disclosure of financial assets [table] Table

*

*

 ifrs-full:DisclosureOfFinancialAssetsTable
1083 Classes of financial assets [axis] Axis ifrs-full:ClassesOfFinancialAssetsAxis
1084 Financial assets Member ifrs-full:FinancialAssetsMember
1085 Trading securities Member ifrs-full:TradingSecuritiesMember
1086 Securities purchased under agreement to resell Member wbk:SecuritiesPurchasedUnderAgreementToResellMember
1087 Other financial assets designated at fair value Member wbk:OtherFinancialAssetsDesignatedAtFairValueMember
1088 Classes of financial instruments [axis] Axis ifrs-full:ClassesOfFinancialInstrumentsAxis
1089 Financial instruments, class [member] Member ifrs-full:ClassesOfFinancialInstrumentsMember
1090 Government and semi-government securities Member wbk:GovernmentAndSemiGovernmentSecuritiesMember
1091 Other debt securities Member wbk:TradingOtherDebtSecuritiesMember
1092 Equity securities Member ifrs-full:OtherEquitySecuritiesMember
1093 Other Member wbk:OtherFinancialInstrumentsMember
1094 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
1095 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
1096 Parent Entity Member us-gaap:ParentCompanyMember
1097 Financial assets LineItems ifrs-full:DisclosureOfFinancialAssetsLineItems
1098 Total trading securities and financial assets designated at fair value Concept (Monetary) As Of Debit ifrs-full:FinancialAssetsAtFairValueThroughProfitOrLoss
1099 41201 - Disclosure - Available-for-sale securities by type (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureAvailableForSaleSecuritiesByTypeDetails
1100 Disclosure of financial assets [table] Table

*

*

 ifrs-full:DisclosureOfFinancialAssetsTable
1101 Classes of financial instruments [axis] Axis ifrs-full:ClassesOfFinancialInstrumentsAxis
1102 Financial instruments, class [member] Member ifrs-full:ClassesOfFinancialInstrumentsMember
1103 Government and semi-government securities Member wbk:GovernmentAndSemiGovernmentSecuritiesMember
1104 Other debt securities Member wbk:TradingOtherDebtSecuritiesMember
1105 Equity securities Member ifrs-full:OtherEquitySecuritiesMember
1106 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
1107 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
1108 Parent Entity Member us-gaap:ParentCompanyMember
1109 Financial assets LineItems ifrs-full:DisclosureOfFinancialAssetsLineItems
1110 Available-for-sale securities measured at cost Concept (Monetary) As Of Debit wbk:FinancialAssetsAvailableForSaleMeasuredAtCost
1111 Available-for-sale securities Concept (Monetary) As Of Debit ifrs-full:FinancialAssetsAvailableforsale
1112 41202 - Disclosure - Available-for-sale securities by contractual maturity (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureAvailableForSaleSecuritiesByContractualMaturityDetails
1113 Disclosure of financial assets [table] Table

*

*

 ifrs-full:DisclosureOfFinancialAssetsTable
1114 Classes of financial instruments [axis] Axis ifrs-full:ClassesOfFinancialInstrumentsAxis
1115 Financial instruments, class [member] Member ifrs-full:ClassesOfFinancialInstrumentsMember
1116 Government and semi-government securities Member wbk:GovernmentAndSemiGovernmentSecuritiesMember
1117 Other debt securities Member wbk:TradingOtherDebtSecuritiesMember
1118 Equity securities Member ifrs-full:OtherEquitySecuritiesMember
1119 Maturity [axis] Axis ifrs-full:MaturityAxis
1120 Aggregated time bands [member] Member ifrs-full:AggregatedTimeBandsMember
1121 No later than one year Member ifrs-full:NotLaterThanOneYearMember
1122 Over 1 Year to 5 Years Member ifrs-full:LaterThanOneYearAndNotLaterThanFiveYearsMember
1123 Over 5 Years to 10 Years Member ifrs-full:LaterThanFiveYearsAndNotLaterThanTenYearsMember
1124 No Specific Maturity Member wbk:NoSpecificMaturityMember
1125 Financial assets LineItems ifrs-full:DisclosureOfFinancialAssetsLineItems
1126 Tax-exempt securities Concept (Monetary) As Of Debit wbk:FinancialAssetsAvailableForSaleTaxExempt
1127 Available-for-sale securities, maturities Concept (Monetary) As Of Debit wbk:FinancialAssetsAvailableForSaleContractualMaturityAmount
1128 Weighted average yield Concept (Percent) As Of wbk:FinancialAssetsAvailableForSaleWeightedAverageYield
1129 41203 - Disclosure - Available-for-sale securities, additional details (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureAvailableForSaleSecuritiesAdditionalDetailsDetails
1130 Disclosure of financial assets [table] Table

*

*

 ifrs-full:DisclosureOfFinancialAssetsTable
1131 Classes of financial instruments [axis] Axis ifrs-full:ClassesOfFinancialInstrumentsAxis
1132 Financial instruments, class [member] Member ifrs-full:ClassesOfFinancialInstrumentsMember
1133 US Government treasury notes Member wbk:UsGovernmentTreasuryNoteMember
1134 Queensland Treasury Corporation Member wbk:QueenslandTreasuryCorporationNotesMember
1135 Australian Commonwealth Government Member wbk:AustralianCommonwealthGovernmentNotesMember
1136 Financial assets LineItems ifrs-full:DisclosureOfFinancialAssetsLineItems
1137 Available-for-sale securities Concept (Monetary) As Of Debit ifrs-full:FinancialAssetsAvailableforsale
1138 Debt securities with aggregate book value exceeding 10% of equity attributable to Westpac's owners Concept (Monetary) As Of Debit wbk:FinancialAssetsAvailableForSaleDebtSecuritiesWithAggregateBookValueExceedingTenPercentOfEquity
1139 41301 - Disclosure - Loans - By location of booking office and product type (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureLoansByLocationOfBookingOfficeAndProductTypeDetails
1140 Disclosure of financial assets [table] Table

*

*

 ifrs-full:DisclosureOfFinancialAssetsTable
1141 Geographical areas [axis] Axis ifrs-full:GeographicalAreasAxis
1142 Geographical areas [member] Member ifrs-full:GeographicalAreasMember
1143 Australia Member country:AU
1144 New Zealand Member country:NZ
1145 Other Overseas Member wbk:OtherOverseasMember
1146 Products and services [axis] Axis ifrs-full:ProductsAndServicesAxis
1147 Products and services [member] Member ifrs-full:ProductsAndServicesMember
1148 Housing Member wbk:HousingLoansMember
1149 Personal (loans and cards) Member wbk:PersonalLoansAndCardsMember
1150 Business Member wbk:BusinessLoansMember
1151 Margin lending Member wbk:MarginLendingLoansMember
1152 Trade finance Member ifrs-full:TradeReceivablesMember
1153 Other Member wbk:OtherLoansMember
1154 Carrying amount, accumulated depreciation, amortisation and impairment and gross carrying amount [axis] Axis ifrs-full:CarryingAmountAccumulatedDepreciationAmortisationAndImpairmentAndGrossCarryingAmountAxis
1155 Carrying amount [member] Member ifrs-full:CarryingAmountMember
1156 Gross/Cost Member ifrs-full:GrossCarryingAmountMember
1157 Provision for impairment charges on loans Member ifrs-full:AllowanceForCreditLossesMember
1158 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
1159 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
1160 Parent Entity Member us-gaap:ParentCompanyMember
1161 Classes of financial assets [axis] Axis ifrs-full:ClassesOfFinancialAssetsAxis
1162 Financial assets Member ifrs-full:FinancialAssetsMember
1163 Fixed rate bills designated at fair value to reduce an accounting mismatch Member wbk:FixedRateBillsDesignatedAtFairValueMember
1164 Financial assets LineItems ifrs-full:DisclosureOfFinancialAssetsLineItems
1165 Loans Concept (Monetary) As Of Debit ifrs-full:LoansAndReceivables
1166 Change in fair value attributable to credit risk recognised during the year Concept (Monetary) For Period Debit ifrs-full:ChangesInFairValueOfLoansOrReceivablesAttributableToChangesInCreditRiskOfFinancialAssets
1167 Cumulative change in fair value attributable to credit risk Concept (Monetary) As Of Debit ifrs-full:AccumulatedChangesInFairValueOfLoanOrReceivableAttributableToChangesInCreditRiskOfFinancialAssets
1168 Securitised loans Concept (Monetary) As Of Debit wbk:SecuritisedLoans
1169 41302 - Disclosure - Loans - Finance lease receivables included in loans (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureLoansFinanceLeaseReceivablesIncludedInLoansDetails
1170 Disclosure of financial assets [table] Table

*

*

 ifrs-full:DisclosureOfFinancialAssetsTable
1171 Maturity [axis] Axis ifrs-full:MaturityAxis
1172 Aggregated time bands [member] Member ifrs-full:AggregatedTimeBandsMember
1173 No later than one year Member ifrs-full:NotLaterThanOneYearMember
1174 Over 1 Year to 5 Years Member ifrs-full:LaterThanOneYearAndNotLaterThanFiveYearsMember
1175 Over 5 Years Member ifrs-full:LaterThanFiveYearsMember
1176 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
1177 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
1178 Parent Entity Member us-gaap:ParentCompanyMember
1179 Financial assets LineItems ifrs-full:DisclosureOfFinancialAssetsLineItems
1180 Gross investment in finance lease receivables Concept (Monetary) As Of Debit ifrs-full:GrossInvestmentInFinanceLease
1181 Unearned future finance income on finance lease receivables Concept (Monetary) As Of Debit ifrs-full:UnearnedFinanceIncomeOnFinanceLease
1182 Net investment in finance lease receivables Concept (Monetary) As Of Debit ifrs-full:NetInvestmentInFinanceLease
1183 Accumulated allowance for uncollectable minimum lease payments Concept (Monetary) As Of Credit ifrs-full:AccumulatedAllowanceForUncollectibleMinimumLeasePaymentsReceivable
1184 Net investment in finance lease receivables after accumulated allowance Concept (Monetary) As Of Debit wbk:NetInvestmentInFinanceLeaseAfterAccumulatedAllowance
1185 41303 - Disclosure - Loans - Presented based on industry classification (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureLoansPresentedBasedOnIndustryClassificationDetails
1186 Disclosure of financial assets [table] Table

*

*

 ifrs-full:DisclosureOfFinancialAssetsTable
1187 IFRS Industry of Counterparty, Type [Axis] Axis wbk:IfrsIndustryOfCounterpartyTypeAxis
1188 IFRS Industry of Counterparty [Domain] Member wbk:IfrsIndustryOfCounterpartyDomain
1189 Accommodation, cafes and restaurants Member wbk:AccommodationCafesAndRestaurantsMember
1190 Agriculture, forestry and fishing Member wbk:AgricultureForestryAndFishingMember
1191 Construction Member wbk:ConstructionMember
1192 Finance and insurance Member wbk:FinanceAndInsuranceMember
1193 Government, administration and defence Member wbk:GovernmentAdministrationAndDefenceMember
1194 Manufacturing Member wbk:ManufacturingMember
1195 Mining Member wbk:MiningMember
1196 Property Member wbk:PropertyMember
1197 Property services and business services Member wbk:PropertyServicesAndBusinessServicesMember
1198 Services Member wbk:ServicesMember
1199 Trade Member wbk:TradeMember
1200 Transport and storage Member wbk:TransportAndStorageMember
1201 Utilities Member wbk:UtilitiesMember
1202 Retail lending Member wbk:RetailLendingMember
1203 Other Member wbk:OtherIndustryMember
1204 Geographical areas [axis] Axis ifrs-full:GeographicalAreasAxis
1205 Geographical areas [member] Member ifrs-full:GeographicalAreasMember
1206 Australia Member country:AU
1207 New Zealand Member country:NZ
1208 Other Overseas Member wbk:OtherOverseasMember
1209 Carrying amount, accumulated depreciation, amortisation and impairment and gross carrying amount [axis] Axis ifrs-full:CarryingAmountAccumulatedDepreciationAmortisationAndImpairmentAndGrossCarryingAmountAxis
1210 Carrying amount [member] Member ifrs-full:CarryingAmountMember
1211 Gross/Cost Member ifrs-full:GrossCarryingAmountMember
1212 Provision for impairment charges on loans Member ifrs-full:AllowanceForCreditLossesMember
1213 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
1214 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
1215 Parent Entity Member us-gaap:ParentCompanyMember
1216 Financial assets LineItems ifrs-full:DisclosureOfFinancialAssetsLineItems
1217 Loans Concept (Monetary) As Of Debit ifrs-full:LoansAndReceivables
1218 41304 - Disclosure - Loans - Consolidated contractual maturity distribution (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureLoansConsolidatedContractualMaturityDistributionDetails
1219 Disclosure of financial assets [table] Table

*

*

 ifrs-full:DisclosureOfFinancialAssetsTable
1220 IFRS Industry of Counterparty, Type [Axis] Axis wbk:IfrsIndustryOfCounterpartyTypeAxis
1221 IFRS Industry of Counterparty [Domain] Member wbk:IfrsIndustryOfCounterpartyDomain
1222 Accommodation, cafes and restaurants Member wbk:AccommodationCafesAndRestaurantsMember
1223 Agriculture, forestry and fishing Member wbk:AgricultureForestryAndFishingMember
1224 Construction Member wbk:ConstructionMember
1225 Finance and insurance Member wbk:FinanceAndInsuranceMember
1226 Government, administration and defence Member wbk:GovernmentAdministrationAndDefenceMember
1227 Manufacturing Member wbk:ManufacturingMember
1228 Mining Member wbk:MiningMember
1229 Property Member wbk:PropertyMember
1230 Property services and business services Member wbk:PropertyServicesAndBusinessServicesMember
1231 Services Member wbk:ServicesMember
1232 Trade Member wbk:TradeMember
1233 Transport and storage Member wbk:TransportAndStorageMember
1234 Utilities Member wbk:UtilitiesMember
1235 Retail lending Member wbk:RetailLendingMember
1236 Other Member wbk:OtherIndustryMember
1237 Maturity [axis] Axis ifrs-full:MaturityAxis
1238 Aggregated time bands [member] Member ifrs-full:AggregatedTimeBandsMember
1239 No later than one year Member ifrs-full:NotLaterThanOneYearMember
1240 Over 1 Year to 5 Years Member ifrs-full:LaterThanOneYearAndNotLaterThanFiveYearsMember
1241 Over 5 Years Member ifrs-full:LaterThanFiveYearsMember
1242 Geographical areas [axis] Axis ifrs-full:GeographicalAreasAxis
1243 Geographical areas [member] Member ifrs-full:GeographicalAreasMember
1244 Australia Member ifrs-full:CountryOfDomicileMember
1245 Overseas Member ifrs-full:ForeignCountriesMember
1246 Financial assets LineItems ifrs-full:DisclosureOfFinancialAssetsLineItems
1247 Loans and receivables, contractual maturity amount Concept (Monetary) As Of Debit wbk:LoansAndReceivablesContractualMaturityAmount
1248 41305 - Disclosure - Loans - Interest rate segmentation (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureLoansInterestRateSegmentationDetails
1249 Disclosure of financial assets [table] Table

*

*

 ifrs-full:DisclosureOfFinancialAssetsTable
1250 Maturity [axis] Axis ifrs-full:MaturityAxis
1251 Aggregated time bands [member] Member ifrs-full:AggregatedTimeBandsMember
1252 Over 1 Year Member ifrs-full:LaterThanOneYearMember
1253 Geographical areas [axis] Axis ifrs-full:GeographicalAreasAxis
1254 Geographical areas [member] Member ifrs-full:GeographicalAreasMember
1255 Australia Member ifrs-full:CountryOfDomicileMember
1256 Overseas Member ifrs-full:ForeignCountriesMember
1257 Types of interest rates [axis] Axis ifrs-full:TypesOfInterestRatesAxis
1258 Interest rate types [member] Member ifrs-full:InterestRateTypesMember
1259 Variable Interest Rates Member ifrs-full:FloatingInterestRateMember
1260 Fixed interest rate Member ifrs-full:FixedInterestRateMember
1261 Financial assets LineItems ifrs-full:DisclosureOfFinancialAssetsLineItems
1262 Loans and receivables, contractual maturity amount Concept (Monetary) As Of Debit wbk:LoansAndReceivablesContractualMaturityAmount
1263 41401 - Disclosure - Provisions for impairment charges - Reconciliation (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureProvisionsForImpairmentChargesReconciliationDetails
1264 Disclosure of financial assets [table] Table

*

*

 ifrs-full:DisclosureOfFinancialAssetsTable
1265 Method of assessment of expected credit losses [axis] Axis ifrs-full:MethodOfAssessmentOfExpectedCreditLossesAxis
1266 Method of assessment of expected credit losses [member] Member ifrs-full:MethodOfAssessmentOfExpectedCreditLossesMember
1267 Individually assessed Member ifrs-full:ExpectedCreditLossesIndividuallyAssessedMember
1268 Collectively assessed Member ifrs-full:ExpectedCreditLossesCollectivelyAssessedMember
1269 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
1270 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
1271 Parent Entity Member us-gaap:ParentCompanyMember
1272 Financial assets LineItems ifrs-full:DisclosureOfFinancialAssetsLineItems
1273 Provisions for impairment charges on loans and credit commitments Abstract ifrs-full:ReconciliationOfChangesInAllowanceAccountForCreditLossesOfFinancialAssetsAbstract
1274 Opening balance Concept (Monetary) As Of Credit ifrs-full:AllowanceAccountForCreditLossesOfFinancialAssets
1275 Provisions raised Concept (Monetary) For Period ifrs-full:ImpairmentLossRecognisedInProfitOrLossLoansAndAdvances
1276 Write-backs Concept (Monetary) For Period ifrs-full:ReversalOfImpairmentLossRecognisedInProfitOrLossLoansAndAdvances
1277 Write-offs Concept (Monetary) For Period Debit ifrs-full:UtilisationAllowanceAccountForCreditLossesOfFinancialAssets
1278 Interest adjustment Concept (Monetary) For Period Credit ifrs-full:IncreaseDecreaseThroughAdjustmentsArisingFromPassageOfTimeAllowanceAccountForCreditLossesOfFinancialAssets
1279 Other adjustments Concept (Monetary) For Period Credit ifrs-full:IncreaseDecreaseThroughOtherChangesAllowanceAccountForCreditLossesOfFinancialAssets
1280 Closing balance Concept (Monetary) As Of Credit ifrs-full:AllowanceAccountForCreditLossesOfFinancialAssets
1281 41402 - Disclosure - Provisions for impairment charges - Balances (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureProvisionsForImpairmentChargesBalancesDetails
1282 Disclosure of financial assets [table] Table

*

*

 ifrs-full:DisclosureOfFinancialAssetsTable
1283 Classes of financial assets [axis] Axis ifrs-full:ClassesOfFinancialAssetsAxis
1284 Financial assets Member ifrs-full:FinancialAssetsMember
1285 Loans Member wbk:LoansAndFinanceLeasesReceivableMember
1286 Classes of other provisions [axis] Axis ifrs-full:ClassesOfProvisionsAxis
1287 Other provisions Member ifrs-full:OtherProvisionsMember
1288 Provisions for Impairment on Credit Commitments Member ifrs-full:ProvisionForCreditCommitmentsMember
1289 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
1290 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
1291 Parent Entity Member us-gaap:ParentCompanyMember
1292 Financial assets LineItems ifrs-full:DisclosureOfFinancialAssetsLineItems
1293 Provisions for impairment charges on loans and credit commitments Abstract ifrs-full:ReconciliationOfChangesInAllowanceAccountForCreditLossesOfFinancialAssetsAbstract
1294 Provisions for impairment charges and credit commitments Concept (Monetary) As Of Credit ifrs-full:AllowanceAccountForCreditLossesOfFinancialAssets
1295 41403 - Disclosure - Provisions for impairment charges - Industry classification (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureProvisionsForImpairmentChargesIndustryClassificationDetails
1296 Disclosure of financial assets [table] Table

*

*

 ifrs-full:DisclosureOfFinancialAssetsTable
1297 Method of assessment of expected credit losses [axis] Axis ifrs-full:MethodOfAssessmentOfExpectedCreditLossesAxis
1298 Method of assessment of expected credit losses [member] Member ifrs-full:MethodOfAssessmentOfExpectedCreditLossesMember
1299 Individually assessed Member ifrs-full:ExpectedCreditLossesIndividuallyAssessedMember
1300 Collectively assessed Member ifrs-full:ExpectedCreditLossesCollectivelyAssessedMember
1301 IFRS Industry of Counterparty, Type [Axis] Axis wbk:IfrsIndustryOfCounterpartyTypeAxis
1302 IFRS Industry of Counterparty [Domain] Member wbk:IfrsIndustryOfCounterpartyDomain
1303 Accommodation, cafes and restaurants Member wbk:AccommodationCafesAndRestaurantsMember
1304 Agriculture, forestry and fishing Member wbk:AgricultureForestryAndFishingMember
1305 Construction Member wbk:ConstructionMember
1306 Finance and insurance Member wbk:FinanceAndInsuranceMember
1307 Manufacturing Member wbk:ManufacturingMember
1308 Mining Member wbk:MiningMember
1309 Property Member wbk:PropertyMember
1310 Property services and business services Member wbk:PropertyServicesAndBusinessServicesMember
1311 Services Member wbk:ServicesMember
1312 Trade Member wbk:TradeMember
1313 Transport and storage Member wbk:TransportAndStorageMember
1314 Utilities Member wbk:UtilitiesMember
1315 Retail lending Member wbk:RetailLendingMember
1316 Other Member wbk:OtherIndustryMember
1317 Geographical areas [axis] Axis ifrs-full:GeographicalAreasAxis
1318 Geographical areas [member] Member ifrs-full:GeographicalAreasMember
1319 Australia Member country:AU
1320 New Zealand Member country:NZ
1321 Other Overseas Member wbk:OtherOverseasMember
1322 Financial assets LineItems ifrs-full:DisclosureOfFinancialAssetsLineItems
1323 Provisions for impairment charges and credit commitments Concept (Monetary) As Of Credit ifrs-full:AllowanceAccountForCreditLossesOfFinancialAssets
1324 Percentage of provision for impairment charges and credit commitments Concept (Percent) As Of wbk:AllowancePercentageForCreditLossesOfFinancialAssets
1325 41404 - Disclosure - Provisions for impairment charges - Write-offs and recoveries (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureProvisionsForImpairmentChargesWriteOffsAndRecoveriesDetails
1326 Disclosure of financial assets [table] Table

*

*

 ifrs-full:DisclosureOfFinancialAssetsTable
1327 Method of assessment of expected credit losses [axis] Axis ifrs-full:MethodOfAssessmentOfExpectedCreditLossesAxis
1328 Method of assessment of expected credit losses [member] Member ifrs-full:MethodOfAssessmentOfExpectedCreditLossesMember
1329 Individually assessed Member ifrs-full:ExpectedCreditLossesIndividuallyAssessedMember
1330 Collectively assessed Member ifrs-full:ExpectedCreditLossesCollectivelyAssessedMember
1331 IFRS Industry of Counterparty, Type [Axis] Axis wbk:IfrsIndustryOfCounterpartyTypeAxis
1332 IFRS Industry of Counterparty [Domain] Member wbk:IfrsIndustryOfCounterpartyDomain
1333 Accommodation, cafes and restaurants Member wbk:AccommodationCafesAndRestaurantsMember
1334 Agriculture, forestry and fishing Member wbk:AgricultureForestryAndFishingMember
1335 Construction Member wbk:ConstructionMember
1336 Finance and insurance Member wbk:FinanceAndInsuranceMember
1337 Manufacturing Member wbk:ManufacturingMember
1338 Mining Member wbk:MiningMember
1339 Property Member wbk:PropertyMember
1340 Property services and business services Member wbk:PropertyServicesAndBusinessServicesMember
1341 Services Member wbk:ServicesMember
1342 Trade Member wbk:TradeMember
1343 Transport and storage Member wbk:TransportAndStorageMember
1344 Utilities Member wbk:UtilitiesMember
1345 Retail lending Member wbk:RetailLendingMember
1346 Other Member wbk:OtherIndustryMember
1347 Geographical areas [axis] Axis ifrs-full:GeographicalAreasAxis
1348 Geographical areas [member] Member ifrs-full:GeographicalAreasMember
1349 Australia Member country:AU
1350 New Zealand Member country:NZ
1351 Other Overseas Member wbk:OtherOverseasMember
1352 Financial assets LineItems ifrs-full:DisclosureOfFinancialAssetsLineItems
1353 Write-offs Concept (Monetary) For Period Debit ifrs-full:UtilisationAllowanceAccountForCreditLossesOfFinancialAssets
1354 Recoveries Concept (Monetary) For Period Credit ifrs-full:GainOnRecoveryOfLoansAndAdvancesPreviouslyWrittenOff
1355 Net write-offs and recoveries Concept (Monetary) For Period Debit wbk:UtilisationNetOfRecoveriesAllowanceAccountForCreditLossesOfFinancialAssets
1356 41501 - Disclosure - Life insurance assets and life insurance liabilities - Assets (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureLifeInsuranceAssetsAndLifeInsuranceLiabilitiesAssetsDetails
1357 Disclosure of types of insurance contracts [table] Table

*

*

 ifrs-full:DisclosureOfTypesOfInsuranceContractsTable
1358 Classes of assets [axis] Axis ifrs-full:ClassesOfAssetsAxis
1359 Assets [member] Member ifrs-full:ClassesOfAssetsMember
1360 Equity instruments Member ifrs-full:EquityInvestmentsMember
1361 Debt instruments Member ifrs-full:DebtSecuritiesMember
1362 Unit trusts Member wbk:UnitTrustsMember
1363 Loans and other assets Member wbk:LoansAndOtherAssetsMember
1364 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
1365 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
1366 Parent Entity Member us-gaap:ParentCompanyMember
1367 Disclosure of life insurance assets LineItems ifrs-full:DisclosureOfTypesOfInsuranceContractsLineItems
1368 Life insurance assets Concept (Monetary) As Of Debit wbk:LifeInsuranceAssets
1369 41502 - Disclosure - Life insurance assets and life insurance liabilities - Liabilities (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureLifeInsuranceAssetsAndLifeInsuranceLiabilitiesLiabilitiesDetails
1370 Disclosure of types of insurance contracts [table] Table

*

*

 ifrs-full:DisclosureOfTypesOfInsuranceContractsTable
1371 Types of insurance contracts [axis] Axis ifrs-full:TypesOfInsuranceContractsAxis
1372 Types of insurance contracts [member] Member ifrs-full:InsuranceContractsMember
1373 Life Investment Contracts Member wbk:LifeInvestmentContractsMember
1374 Life insurance Member ifrs-full:LifeInsuranceContractsMember
1375 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
1376 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
1377 Parent Entity Member us-gaap:ParentCompanyMember
1378 Disclosure of life insurance liabilities LineItems ifrs-full:DisclosureOfTypesOfInsuranceContractsLineItems
1379 Reconciliation of movements in policy liabilities Abstract ifrs-full:ReconciliationOfChangesInLiabilitiesUnderInsuranceContractsAndReinsuranceContractsIssuedAbstract
1380 Liabilities under insurance contracts and reinsurance contracts issued at beginning of period Concept (Monetary) As Of Credit ifrs-full:LiabilitiesArisingFromInsuranceContracts
1381 Movements in policy liabilities reflected in the income statement Concept (Monetary) For Period Credit ifrs-full:ExpenseIncomeIncludedInProfitOrLossLiabilitiesUnderInsuranceContractsAndReinsuranceContractsIssued
1382 Contract contributions recognised in policy liabilities Concept (Monetary) For Period Credit ifrs-full:AdditionsLiabilitiesUnderInsuranceContractsAndReinsuranceContractsIssued
1383 Contract withdrawals recognised in policy liabilities Concept (Monetary) For Period Debit ifrs-full:CashPaidLiabilitiesUnderInsuranceContractsAndReinsuranceContractsIssued
1384 Contract fees, expenses and tax recoveries Concept (Monetary) For Period Debit wbk:DecreaseThroughContractFeesExpensesAndTaxRecoveriesLiabilitiesUnderInsuranceContractsAndReinsuranceContractIssued
1385 Change in external unit holders of managed investment schemes Concept (Monetary) For Period Debit wbk:DecreaseThroughChangeInInvestmentSchemesLiabilitiesUnderInsuranceContractsAndReinsuranceContractIssued
1386 Liabilities under insurance contracts and reinsurance contracts issued at end of period Concept (Monetary) As Of Credit ifrs-full:LiabilitiesArisingFromInsuranceContracts
1387 41601 - Disclosure - Payables due to other financial institutions (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosurePayablesDueToOtherFinancialInstitutionsDetails
1388 Payables Due to Other Financial Institutions [Table] Table

*

*

 wbk:PayablesDueToOtherFinancialInstitutionsTable
1389 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
1390 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
1391 Parent Entity Member us-gaap:ParentCompanyMember
1392 Classes of liabilities [axis] Axis ifrs-full:ClassesOfLiabilitiesAxis
1393 Liabilities [member] Member ifrs-full:LiabilitiesMember
1394 Payables due to other financial institutions Member wbk:PayablesDueToOtherFinancialInstitutionsMember
1395 Payables due to other financial institutions LineItems wbk:PayablesDueToOtherFinancialInstitutionsLineItems
1396 Cash collateral Concept (Monetary) As Of Credit wbk:CashCollateralDueToOtherFinancialInstitutions
1397 Liabilities due to central banks Concept (Monetary) As Of Credit ifrs-full:LiabilitiesDueToCentralBanks
1398 Interbank borrowing Concept (Monetary) As Of Credit wbk:InterbankBorrowing
1399 Security repurchase agreements Concept (Monetary) As Of Credit wbk:SecuritiesSoldUnderAgreementsToRepurchaseRepurchaseLiabilityDueToOtherFinancialInstitutions
1400 Total payables due to other financial institutions Concept (Monetary) As Of Credit wbk:PayablesDueToOtherFinancialInstitutions
1401 Carrying value of securities pledged under repurchase agreements Concept (Monetary) As Of Debit wbk:SecuritiesPledgedForRepurchaseAgreements
1402 41701 - Disclosure - Deposits and other borrowings - Total deposits and other borrowings (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureDepositsAndOtherBorrowingsTotalDepositsAndOtherBorrowingsDetails
1403 Disclosure of Deposits and Other Borrowings [Table] Table

*

*

 wbk:DisclosureOfDepositsAndOtherBorrowingsTable
1404 Geographical areas [axis] Axis ifrs-full:GeographicalAreasAxis
1405 Geographical areas [member] Member ifrs-full:GeographicalAreasMember
1406 Australia Member country:AU
1407 New Zealand Member country:NZ
1408 Other Overseas Member wbk:OtherOverseasMember
1409 Measurement [axis] Axis ifrs-full:MeasurementAxis
1410 Aggregated measurement [member] Member ifrs-full:AggregatedMeasurementMember
1411 At fair value Member ifrs-full:AtFairValueMember
1412 At amortised cost Member wbk:AtAmortisedCostMember
1413 Classes of liabilities [axis] Axis ifrs-full:ClassesOfLiabilitiesAxis
1414 Liabilities [member] Member ifrs-full:LiabilitiesMember
1415 Certificates of deposit Member wbk:IfrsCertificatesOfDepositMember
1416 Non-interest bearing, repayable at call Member wbk:NonInterestBearingRepayableAtCallMember
1417 Other interest bearing at call Member wbk:OtherInterestBearingAtCallMember
1418 Other interest bearing term Member wbk:OtherInterestBearingTermMember
1419 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
1420 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
1421 Parent Entity Member us-gaap:ParentCompanyMember
1422 Deposits and other borrowings LineItems wbk:DisclosureOfDepositsAndOtherBorrowingsLineItems
1423 Total deposits and other borrowings Concept (Monetary) As Of Credit wbk:DepositsAndOtherBorrowings
1424 Contractual outstanding amount payable at maturity Concept (Monetary) As Of Credit wbk:ContractualOutstandingAmountsPayableAtMaturityForDepositsAndOtherBorrowingsAtFairValue
1425 41702 - Disclosure - Deposits and other borrowings - Average balances and average rates for major categories of deposits (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureDepositsAndOtherBorrowingsAverageBalancesAndAverageRatesForMajorCategoriesOfDepositsDetails
1426 Disclosure of Deposits and Other Borrowings [Table] Table

*

*

 wbk:DisclosureOfDepositsAndOtherBorrowingsTable
1427 Classes of liabilities [axis] Axis ifrs-full:ClassesOfLiabilitiesAxis
1428 Liabilities [member] Member ifrs-full:LiabilitiesMember
1429 Non-interest bearing, repayable at call Member wbk:NonInterestBearingRepayableAtCallMember
1430 Certificates of deposit Member wbk:IfrsCertificatesOfDepositMember
1431 Other interest bearing at call Member wbk:OtherInterestBearingAtCallMember
1432 Other interest bearing term Member wbk:OtherInterestBearingTermMember
1433 Geographical areas [axis] Axis ifrs-full:GeographicalAreasAxis
1434 Geographical areas [member] Member ifrs-full:GeographicalAreasMember
1435 Australia Member ifrs-full:CountryOfDomicileMember
1436 Overseas Member ifrs-full:ForeignCountriesMember
1437 Deposits and other borrowings LineItems wbk:DisclosureOfDepositsAndOtherBorrowingsLineItems
1438 Average Balance Concept (Monetary) As Of Credit wbk:AverageBalancesOfDeposits
1439 Average Rate Concept (Percent) For Period wbk:AverageInterestRateOnDeposits
1440 41703 - Disclosure - Deposits and other borrowings - Certificates of deposit and term deposits (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureDepositsAndOtherBorrowingsCertificatesOfDepositAndTermDepositsDetails
1441 Disclosure of Deposits and Other Borrowings [Table] Table

*

*

 wbk:DisclosureOfDepositsAndOtherBorrowingsTable
1442 Maturity [axis] Axis ifrs-full:MaturityAxis
1443 Aggregated time bands [member] Member ifrs-full:AggregatedTimeBandsMember
1444 Less Than 3 Months Member ifrs-full:NotLaterThanThreeMonthsMember
1445 Between 3 and 6 Months Member ifrs-full:LaterThanThreeMonthsAndNotLaterThanSixMonthsMember
1446 Between 6 Months and 1 Year Member ifrs-full:LaterThanSixMonthsAndNotLaterThanOneYearMember
1447 Over 1 Year Member ifrs-full:LaterThanOneYearMember
1448 Geographical areas [axis] Axis ifrs-full:GeographicalAreasAxis
1449 Geographical areas [member] Member ifrs-full:GeographicalAreasMember
1450 Australia Member ifrs-full:CountryOfDomicileMember
1451 Deposits and other borrowings LineItems wbk:DisclosureOfDepositsAndOtherBorrowingsLineItems
1452 Certificates of deposit greater than US$100,000 Concept (Monetary) As Of Credit wbk:CertificatesOfDepositsMoreThanUs100000
1453 Term deposits greater than US$100,000 Concept (Monetary) As Of Credit wbk:TermDepositsMoreThanUs100000
1454 41801 - Disclosure - Other financial liabilities at fair value through income statement (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureOtherFinancialLiabilitiesAtFairValueThroughIncomeStatementDetails
1455 Disclosure of financial liabilities [table] Table

*

*

 ifrs-full:DisclosureOfFinancialLiabilitiesTable
1456 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
1457 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
1458 Parent Entity Member us-gaap:ParentCompanyMember
1459 Classes of liabilities [axis] Axis ifrs-full:ClassesOfLiabilitiesAxis
1460 Liabilities [member] Member ifrs-full:LiabilitiesMember
1461 Other financial liabilities at fair value through income statement Member wbk:OtherFinancialLiabilitiesAtFairValueThroughProfitOrLossMember
1462 Other financial liabilities at fair value through income statement LineItems ifrs-full:DisclosureOfFinancialLiabilitiesLineItems
1463 Security repurchase agreements Concept (Monetary) As Of Credit wbk:SecuritiesSoldUnderAgreementsToRepurchaseRepurchaseLiabilityInTradingPortfolio
1464 Securities sold short Concept (Monetary) As Of Credit wbk:SecuritiesSoldNotYetPurchased
1465 Total other financial liabilities at fair value through income statement Concept (Monetary) As Of Credit ifrs-full:FinancialLiabilitiesAtFairValueThroughProfitOrLoss
1466 Carrying value of securities pledged under repurchase agreements Concept (Monetary) As Of Debit wbk:SecuritiesPledgedForRepurchaseAgreements
1467 41901 - Disclosure - Debt issues - Balances (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureDebtIssuesBalancesDetails
1468 Disclosure of detailed information about borrowings [table] Table

*

*

 ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsTable
1469 Borrowings by name [axis] Axis ifrs-full:BorrowingsByNameAxis
1470 Borrowings by name [member] Member ifrs-full:BorrowingsByNameMember
1471 Own issuances Member wbk:OwnIssuancesInstrumentsMember
1472 Customer conduits Member wbk:CustomerConduitsMember
1473 Acceptances Member wbk:AcceptancesMember
1474 Covered bonds Member wbk:CoveredBondsMember
1475 Senior Member wbk:SeniorInstrumentsMember
1476 Securitisation Member wbk:SecuritisationMember
1477 Structured notes Member wbk:StructuredNotesMember
1478 Measurement [axis] Axis ifrs-full:MeasurementAxis
1479 Aggregated measurement [member] Member ifrs-full:AggregatedMeasurementMember
1480 At fair value Member ifrs-full:AtFairValueMember
1481 At amortised cost Member wbk:AtAmortisedCostMember
1482 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
1483 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
1484 Parent Entity Member us-gaap:ParentCompanyMember
1485 Debt issues LineItems ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsLineItems
1486 Short-term debt Concept (Monetary) As Of Credit wbk:ShortTermDebtInstrumentsIssued
1487 Long-term debt Concept (Monetary) As Of Credit wbk:LongTermDebtInstrumentsIssued
1488 Total debt issues Concept (Monetary) As Of Credit ifrs-full:DebtSecurities
1489 41902 - Disclosure - Debt issues - Movement Reconciliation (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureDebtIssuesMovementReconciliationDetails
1490 Disclosure of detailed information about borrowings [table] Table

*

*

 ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsTable
1491 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
1492 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
1493 Parent Entity Member us-gaap:ParentCompanyMember
1494 Debt issues LineItems ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsLineItems
1495 Movement Reconciliation Abstract wbk:ReconciliationOfChangesInDebtSecuritiesAbstract
1496 Balance as at 1 October 2017 Concept (Monetary) As Of Credit ifrs-full:DebtSecurities
1497 Issuances Concept (Monetary) For Period Credit wbk:IssuancesOfDebtSecurities
1498 Maturities, repayments, buy backs and reductions Concept (Monetary) For Period Debit wbk:RedemptionOfDebtSecurities
1499 Total cash movements Concept (Monetary) For Period Credit wbk:IncreaseDecreaseThroughCashMovementsDebtSecurities
1500 Foreign exchange translation impact Concept (Monetary) For Period Credit wbk:IncreaseDecreaseThroughNetExchangeDifferencesDebtSecurities
1501 Fair value adjustments Concept (Monetary) For Period Credit wbk:IncreaseDecreaseThroughFairValueAdjustmentsDebtSecurities
1502 Fair value hedge accounting adjustments Concept (Monetary) For Period Credit wbk:IncreaseDecreaseThroughFairValueHedgeAccountingAdjustmentsDebtSecurities
1503 Other (amortisation of bond issue costs, etc.) Concept (Monetary) For Period Credit wbk:IncreaseDecreaseThroughOtherAdjustmentsDebtSecurities
1504 Total non-cash movements Concept (Monetary) For Period Credit wbk:IncreaseDecreaseThroughNonCashMovementsDebtSecurities
1505 Balance as at 30 September 2018 Concept (Monetary) As Of Credit ifrs-full:DebtSecurities
1506 Contractual outstanding amount payable at maturity Concept (Monetary) As Of Credit wbk:DebtSecuritiesContractualOutstandingAmountPayableAtMaturity
1507 Decrease in fair value of debt issues attributable to changes in entity's own credit risk Concept (Monetary) As Of Credit wbk:CumulativeEffectInFairValueOfDebtSecuritiesCreditRisk
1508 41903 - Disclosure - Debt issues - By currency (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureDebtIssuesByCurrencyDetails
1509 Disclosure of detailed information about borrowings [table] Table

*

*

 ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsTable
1510 Borrowings by name [axis] Axis ifrs-full:BorrowingsByNameAxis
1511 Borrowings by name [member] Member ifrs-full:BorrowingsByNameMember
1512 Own issuances Member wbk:OwnIssuancesInstrumentsMember
1513 US commercial paper Member wbk:UsCommercialPaperMember
1514 Senior debt Member wbk:OwnIssuancesSeniorMember
1515 Asset backed commercial paper Member wbk:AssetBackedCommercialPaperMember
1516 Acceptances Member wbk:AcceptancesMember
1517 Currency [Axis] Axis us-gaap:CurrencyAxis
1518 All Currencies [Domain] Member currency:AllCurrenciesDomain
1519 AUD Member currency:AUD
1520 CHF Member currency:CHF
1521 EUR Member currency:EUR
1522 GBP Member currency:GBP
1523 JPY Member currency:JPY
1524 NZD Member currency:NZD
1525 USD Member currency:USD
1526 Other currencies Member wbk:OtherCurrencyMember
1527 Debt issues LineItems ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsLineItems
1528 Short-term debt Concept (Monetary) As Of Credit wbk:ShortTermDebtInstrumentsIssued
1529 Long-term debt Concept (Monetary) As Of Credit wbk:LongTermDebtInstrumentsIssued
1530 41904 - Disclosure - Debt issues - US commercial paper (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureDebtIssuesUsCommercialPaperDetails
1531 Disclosure of detailed information about borrowings [table] Table

*

*

 ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsTable
1532 Borrowings by name [axis] Axis ifrs-full:BorrowingsByNameAxis
1533 Borrowings by name [member] Member ifrs-full:BorrowingsByNameMember
1534 US commercial paper Member wbk:UsCommercialPaperMember
1535 Debt issues LineItems ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsLineItems
1536 Maximum amount outstanding at any month end, short-term borrowings Concept (Monetary) For Period Credit wbk:MaximumOutstandingAmountShortTermDebtPerMonth
1537 Approximate average amount outstanding, short-term borrowings Concept (Monetary) For Period Credit wbk:AverageOutstandingAmountShortTermDebt
1538 Approximate weighted average interest rate on average amount outstanding, short-term borrowings Concept (Percent) For Period wbk:WeightedAverageInterestRateAverageOutstandingAmountShortTermDebt
1539 Approximate weighted average interest rate on amount outstanding as at end of the year, short-term borrowings Concept (Percent) As Of wbk:WeightedAverageInterestRateOutstandingAmountShortTermDebt
1540 42001 - Disclosure - Loan Capital - Summary (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureLoanCapitalSummaryDetails
1541 Disclosure of detailed information about borrowings [table] Table

*

*

 ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsTable
1542 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
1543 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
1544 Parent Entity Member us-gaap:ParentCompanyMember
1545 Borrowings by name [axis] Axis ifrs-full:BorrowingsByNameAxis
1546 Borrowings by name [member] Member ifrs-full:BorrowingsByNameMember
1547 Additional Tier 1 (AT1) loan capital Member wbk:AdditionalTierOneLoanCapitalMember
1548 Convertible preference shares Member wbk:WestpacConvertiblePreferenceSharesClassifiedAsLiabilityMember
1549 Westpac Capital Notes Member wbk:WestpacCapitalNotesMember
1550 USD AT1 securities Member wbk:UsdAdditionalTierOneSecuritiesMember
1551 Tier 2 loan capital Member wbk:TierTwoLoanCapitalMember
1552 Subordinated notes Member wbk:SubordinatedNotesMember
1553 Subordinated perpetual notes Member wbk:SubordinatedPerpetualNotesMember
1554 Disclosure of detailed information about borrowings [line items] LineItems ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsLineItems
1555 Loan capital Concept (Monetary) As Of Credit wbk:LoanCapital
1556 42002 - Disclosure - Loan Capital - Movement Reconciliation (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureLoanCapitalMovementReconciliationDetails
1557 Disclosure of detailed information about borrowings [table] Table

*

*

 ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsTable
1558 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
1559 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
1560 Parent Entity Member us-gaap:ParentCompanyMember
1561 Loan capital LineItems ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsLineItems
1562 Balance at beginning Concept (Monetary) As Of Credit wbk:LoanCapital
1563 Issuances Concept (Monetary) For Period Credit wbk:LoanCapitalIssuances
1564 Maturities, repayments, buy backs and reductions Concept (Monetary) For Period Debit wbk:LoanCapitalMaturitiesRepaymentsBuyBacksAndReductions
1565 Total cash movements Concept (Monetary) For Period Credit wbk:LoanCapitalTotalCashMovements
1566 Foreign exchange translation impact Concept (Monetary) For Period Credit wbk:LoanCapitalForeignExchangeTranslationImpact
1567 Fair value hedge accounting adjustments Concept (Monetary) For Period Credit wbk:LoanCapitalFairValueHedgeAccountingAdjustments
1568 Conversion of Convertible Preference Shares to ordinary shares Concept (Monetary) For Period Credit wbk:LoanCapitalConversionOfConvertiblePreferenceSharesToOrdinaryShares
1569 Other (amortisation of bond issue costs, etc.) Concept (Monetary) For Period Credit wbk:LoanCapitalOtherNonCashAdjustments
1570 Total non-cash movements Concept (Monetary) For Period Credit wbk:LoanCapitalTotalNonCashMovements
1571 Balance at ending Concept (Monetary) As Of Credit wbk:LoanCapital
1572 42003 - Disclosure - Loan Capital - Additional Tier 1 loan capital (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureLoanCapitalAdditionalTier1LoanCapitalDetails
1573 Disclosure of detailed information about borrowings [table] Table

*

*

 ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsTable
1574 Borrowings by name [axis] Axis ifrs-full:BorrowingsByNameAxis
1575 Borrowings by name [member] Member ifrs-full:BorrowingsByNameMember
1576 Convertible preference shares Member wbk:WestpacConvertiblePreferenceSharesClassifiedAsLiabilityMember
1577 $1,189 million CPS Member wbk:WestpacConvertiblePreferenceShares1189MillionClassifiedAsLiabilityMember
1578 Westpac Capital Notes Member wbk:WestpacCapitalNotesMember
1579 $1,384 million WCN Member wbk:WestpacCapitalNotesOneMember
1580 $1,311 million WCN2 Member wbk:WestpacCapitalNotesTwoMember
1581 $1,324 million WCN3 Member wbk:WestpacCapitalNotesThreeMember
1582 $1,702 million WCN4 Member wbk:WestpacCapitalNotesFourMember
1583 $1,690 million WCN5 Member wbk:WestpacCapitalNotesFiveMember
1584 USD AT1 securities Member wbk:UsdAdditionalTierOneSecuritiesMember
1585 US$1,250 million securities Member wbk:Us1250MillionAdditionalTierOneSecuritiesMember
1586 Types of interest rates [axis] Axis ifrs-full:TypesOfInterestRatesAxis
1587 Interest rate types [member] Member ifrs-full:InterestRateTypesMember
1588 Fixed interest rate Member ifrs-full:FixedInterestRateMember
1589 Variable Interest Rates Member ifrs-full:FloatingInterestRateMember
1590 180 day bank bill rate Member wbk:OneEightZeroDayBankBillRateMember
1591 90 day bank bill rate Member wbk:NinetyDayBankBillRateMember
1592 5-year USD mid-market swap rate Member wbk:FiveYearUsdMidMarketSwapRateMember
1593 Disclosure of detailed information about borrowings [line items] LineItems ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsLineItems
1594 Principal amount Concept (Monetary) As Of ifrs-full:NotionalAmount
1595 Interest rate adjustments (as a percent) Concept (Percent) As Of ifrs-full:BorrowingsAdjustmentToInterestRateBasis
1596 Interest rate (as a percent) Concept (Percent) As Of ifrs-full:BorrowingsInterestRate
1597 Loan capital Concept (Monetary) As Of Credit wbk:LoanCapital
1598 Value of Westpac CPS transferred Concept (Monetary) For Period Debit wbk:ConversionOfLoanCapitalAmountConverted
1599 Value per share of Westpac CPS transferred to nominated party Concept (Share) For Period wbk:ConversionOfLoanCapitalPerShareAmountTransferredToNominatedParty
1600 Shares issued on conversion of Westpac CPS Concept (Shares) For Period wbk:IfrsStockIssuedDuringPeriodSharesConversionOfConvertibleSecurities
1601 42004 - Disclosure - Loan Capital - Additional Tier 1 loan capital - Other (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureLoanCapitalAdditionalTier1LoanCapitalOtherDetails
1602 Disclosure of detailed information about borrowings [table] Table

*

*

 ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsTable
1603 Borrowings by name [axis] Axis ifrs-full:BorrowingsByNameAxis
1604 Borrowings by name [member] Member ifrs-full:BorrowingsByNameMember
1605 Additional Tier 1 (AT1) loan capital Member wbk:AdditionalTierOneLoanCapitalMember
1606 Disclosure of detailed information about borrowings [line items] LineItems ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsLineItems
1607 Number of business days for payment of dividend, distribution or interest Concept (Integer) For Period wbk:NumberOfBusinessDaysForPaymentOfDividendDistributionOrInterest
1608 Number of business days prior to scheduled conversion date to determine share price Concept (Integer) For Period wbk:NumberOfBusinessDaysPriorToScheduledConversionDateToDetermineSharePrice
1609 Discount rate on share price upon conversion Concept (Percent) For Period wbk:DiscountRateOnSharePriceUponConversion
1610 Common Equity Tier 1 Capital ratio, maximum Concept (Percent) For Period wbk:MaximumCommonEquityTierOneCapitalRatio
1611 Number of business days prior to capital trigger event date or non-viability trigger event date to determine share price for conversion Concept (Integer) For Period wbk:NumberOfBusinessDaysPriorToCapitalTriggerEventDateOrNonViabilityTriggerEventDateToDetermineSharePriceForConversion
1612 Discount rate on share price which determined based on capital trigger event date or non-viability trigger event date Concept (Percent) For Period wbk:DiscountRateOnSharePriceWhichDeterminedBasedOnCapitalTriggerEventDateOrNonViabilityTriggerEventDate
1613 Percentage of share price to determine maximum conversion number Concept (Percent) For Period wbk:PercentageOfSharePriceToDetermineMaximumConversionNumber
1614 42005 - Disclosure - Loan Capital - Tier 2 loan capital (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureLoanCapitalTier2LoanCapitalDetails
1615 Disclosure of detailed information about borrowings [table] Table

*

*

 ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsTable
1616 Borrowings by name [axis] Axis ifrs-full:BorrowingsByNameAxis
1617 Borrowings by name [member] Member ifrs-full:BorrowingsByNameMember
1618 Subordinated notes Member wbk:SubordinatedNotesMember
1619 US$350 million subordinated notes Member wbk:WestpacUs350MillionSubordinatedNotesMember
1620 US$800 million subordinated notes Member wbk:WestpacUs800MillionSubordinatedNotesMember
1621 A$925 million subordinated notes Member wbk:WestpacA925MillionSubordinatedNotesMember
1622 A$1,000 million subordinated notes Member wbk:WestpacA1000MillionSubordinatedNotesMember
1623 CNY1,250 million subordinated notes Member wbk:WestpacCny1250MillionSubordinatedNotesMember
1624 A$350 million 4.5% subordinated notes Member wbk:WestpacA350Million4.5PercentSubordinatedNotesMember
1625 S$325 million subordinated notes Member wbk:WestpacS325MillionSubordinatedNotesMember
1626 A$175 million subordinated notes Member wbk:WestpacA175MillionSubordinatedNotesMember
1627 US$100 million subordinated notes Member wbk:WestpacUs100MillionSubordinatedNotesMember
1628 A$700 million subordinated notes Member wbk:WestpacA700MillionSubordinatedNotesMember
1629 JPY20,000 million subordinated notes Member wbk:WestpacJpy20000MillionSubordinatedNotesMember
1630 JPY10,200 million subordinated notes Member wbk:WestpacJpy10200MillionSubordinatedNotesMember
1631 JPY10,000 million subordinated notes Member wbk:WestpacJpy10000MillionSubordinatedNotesMember
1632 NZ$400 million subordinated notes Member wbk:WestpacNz400MillionSubordinatedNotesMember
1633 JPY8,000 million subordinated notes Member wbk:WestpacJpy8000MillionSubordinatedNotesMember
1634 US$1,500 million subordinated notes Member wbk:WestpacUs1500MillionSubordinatedNotesMember
1635 JPY12,000 million subordinated notes Member wbk:WestpacJpy12000MillionSubordinatedNotesMember
1636 JPY13,500 million subordinated notes Member wbk:WestpacJpy13500MillionSubordinatedNotesMember
1637 HKD600 million subordinated notes Member wbk:WestpacJkd600MillionSubordinatedNotesMember
1638 A$350 million 4.334% subordinated notes Member wbk:WestpacA350Million4.334PercentSubordinatedNotesMember
1639 A$185 million subordinated notes Member wbk:Westpac185MillionSubordinatedNotesMember
1640 A$250 million subordinated notes Member wbk:Westpac250MillionSubordinatedNotesMember
1641 A$130 million subordinated notes Member wbk:Westpac130MillionSubordinatedNotesMember
1642 A$725 million subordinated notes Member wbk:Westpac725MillionSubordinatedNotesMember
1643 Types of interest rates [axis] Axis ifrs-full:TypesOfInterestRatesAxis
1644 Interest rate types [member] Member ifrs-full:InterestRateTypesMember
1645 Fixed interest rate Member ifrs-full:FixedInterestRateMember
1646 Variable Interest Rates Member ifrs-full:FloatingInterestRateMember
1647 90 day bank bill rate Member wbk:NinetyDayBankBillRateMember
1648 5-year US Treasury rate Member wbk:FiveYearUsTreasuryRateMember
1649 One year CNH HIBOR reference rate Member wbk:OneYearCnhHiborReferenceRateMember
1650 Five year AUD semi-quarterly mid-swap reference rate Member wbk:FiveYearAudSemiQuarterlyMidSwapReferenceRateMember
1651 Five year SGD swap offer rate Member wbk:FiveYearSgdSwapOfferRateMember
1652 New Zealand 5 year swap rate Member wbk:NewZealandFiveYearSwapRateMember
1653 Five year JPY mid-swap rate Member wbk:FiveYearJpyMidSwapRateMember
1654 5-year USD mid-market swap rate Member wbk:FiveYearUsdMidMarketSwapRateMember
1655 Five year HKD mid-swap rate Member wbk:FiveYearHkdMidSwapRateMember
1656 Disclosure of detailed information about borrowings [line items] LineItems ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsLineItems
1657 Principal amount Concept (Monetary) As Of ifrs-full:NotionalAmount
1658 Interest rate (as a percent) Concept (Percent) As Of ifrs-full:BorrowingsInterestRate
1659 Interest rate adjustments (as a percent) Concept (Percent) As Of ifrs-full:BorrowingsAdjustmentToInterestRateBasis
1660 Loan capital Concept (Monetary) As Of Credit wbk:LoanCapital
1661 42006 - Disclosure - Loan Capital - Tier 2 loan capital - Other (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureLoanCapitalTier2LoanCapitalOtherDetails
1662 Disclosure of detailed information about borrowings [table] Table

*

*

 ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsTable
1663 Borrowings by name [axis] Axis ifrs-full:BorrowingsByNameAxis
1664 Borrowings by name [member] Member ifrs-full:BorrowingsByNameMember
1665 Subordinated notes Member wbk:SubordinatedNotesMember
1666 Disclosure of detailed information about borrowings [line items] LineItems ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsLineItems
1667 Percentage of share price to determine maximum conversion number Concept (Percent) For Period wbk:PercentageOfSharePriceToDetermineMaximumConversionNumber
1668 Number of business days for immediate and irrevocable termination of rights after non-viability trigger event if conversion not occur Concept (Integer) For Period wbk:NumberOfBusinessDaysForImmediateAndIrrevocableTerminationOfRightsAfterNonViabilityTriggerEventIfConversionNotOccur
1669 42007 - Disclosure - Loan Capital - Subordinated perpetual notes (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureLoanCapitalSubordinatedPerpetualNotesDetails
1670 Disclosure of detailed information about borrowings [table] Table

*

*

 ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsTable
1671 Borrowings by name [axis] Axis ifrs-full:BorrowingsByNameAxis
1672 Borrowings by name [member] Member ifrs-full:BorrowingsByNameMember
1673 Subordinated perpetual notes Member wbk:SubordinatedPerpetualNotesMember
1674 Types of interest rates [axis] Axis ifrs-full:TypesOfInterestRatesAxis
1675 Interest rate types [member] Member ifrs-full:InterestRateTypesMember
1676 Variable Interest Rates Member ifrs-full:FloatingInterestRateMember
1677 6 month US$ LIBOR Member wbk:SixMonthUsLiborMember
1678 Disclosure of detailed information about borrowings [line items] LineItems ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsLineItems
1679 Interest rate adjustments (as a percent) Concept (Percent) As Of ifrs-full:BorrowingsAdjustmentToInterestRateBasis
1680 Period prior to payment of dividend on share for payment of interest Concept (xbrli:durationItemType) For Period wbk:PeriodPriorToPaymentOfDividendOnShareForPaymentOfInterest
1681 42101 - Disclosure - Derivative financial instruments - Types of hedges (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureDerivativeFinancialInstrumentsTypesOfHedgesDetails
1682 Disclosure of detailed information about financial instruments [table] Table

*

*

 ifrs-full:DisclosureOfFinancialInstrumentsTable
1683 Types of hedges [axis] Axis ifrs-full:TypesOfHedgesAxis
1684 Hedges [member] Member ifrs-full:TypesOfHedgesMember
1685 Fair-value hedges Member ifrs-full:FairValueHedgesMember
1686 Cash-flow hedges Member ifrs-full:CashFlowHedgesMember
1687 Net Investment Hedging Member ifrs-full:HedgesOfNetInvestmentInForeignOperationsMember
1688 Maturity [axis] Axis ifrs-full:MaturityAxis
1689 Aggregated time bands [member] Member ifrs-full:AggregatedTimeBandsMember
1690 Less than or Up to 1 Month Member ifrs-full:NotLaterThanOneMonthMember
1691 Over 1 Month to 3 Months Member ifrs-full:LaterThanOneMonthAndNotLaterThanThreeMonthsMember
1692 Over 3 Months to 1 Year Member ifrs-full:LaterThanThreeMonthsAndNotLaterThanOneYearMember
1693 1 Year to 2 Years Member ifrs-full:LaterThanOneYearAndNotLaterThanTwoYearsMember
1694 2 Years to 3 Years Member ifrs-full:LaterThanTwoYearsAndNotLaterThanThreeYearsMember
1695 3 Years to 4 Years Member ifrs-full:LaterThanThreeYearsAndNotLaterThanFourYearsMember
1696 4 Years to 5 Years Member ifrs-full:LaterThanFourYearsAndNotLaterThanFiveYearsMember
1697 Over 5 Years Member ifrs-full:LaterThanFiveYearsMember
1698 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
1699 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
1700 Parent Entity Member us-gaap:ParentCompanyMember
1701 Financial instruments LineItems ifrs-full:DisclosureOfFinancialInstrumentsLineItems
1702 Change in fair value hedging instruments Concept (Monetary) For Period Credit ifrs-full:GainsLossesOnHedgingInstrument
1703 Change in fair value hedge items attributed to hedged risk Concept (Monetary) For Period Credit ifrs-full:GainsLossesOnHedgedItemAttributableToHedgedRisk
1704 Ineffectiveness in interest income Concept (Monetary) For Period Credit ifrs-full:GainLossOnChangeInFairValueOfHedgingInstrumentUsedAsBasisForRecognisingHedgeIneffectiveness
1705 Cash inflows Concept (Percent) For Period wbk:DerivativesDesignatedAsCashFlowHedgesPercentageOfCashInflowsToGrossCashFlows
1706 Cash outflows Concept (Percent) For Period wbk:DerivativesDesignatedAsCashFlowHedgesPercentageOfCashOutflowsToGrossCashFlows
1707 Cash flow hedge ineffectiveness Concept (Monetary) For Period Credit ifrs-full:GainsLossesOnIneffectivenessOfCashFlowHedgesRecognisedInProfitOrLoss
1708 Ineffectives of net investment in foreign operations Concept (Monetary) For Period Credit ifrs-full:GainsLossesOnIneffectivenessOfHedgesOfNetInvestmentsInForeignOperations
1709 42102 - Disclosure - Derivative financial instruments - Notional amount and fair value of derivative instruments held for trading and designated in hedge relationships (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureDerivativeFinancialInstrumentsNotionalAmountAndFairValueOfDerivativeInstrumentsHeldForTradingAndDesignatedInHedgeRelationshipsDetails
1710 Disclosure of detailed information about financial instruments [table] Table

*

*

 ifrs-full:DisclosureOfFinancialInstrumentsTable
1711 Types of hedges [axis] Axis ifrs-full:TypesOfHedgesAxis
1712 Hedges [member] Member ifrs-full:TypesOfHedgesMember
1713 Fair-value hedges Member ifrs-full:FairValueHedgesMember
1714 Cash-flow hedges Member ifrs-full:CashFlowHedgesMember
1715 Net Investment Hedging Member ifrs-full:HedgesOfNetInvestmentInForeignOperationsMember
1716 Classes of financial instruments [axis] Axis ifrs-full:ClassesOfFinancialInstrumentsAxis
1717 Financial instruments, class [member] Member ifrs-full:ClassesOfFinancialInstrumentsMember
1718 Derivatives - net Member ifrs-full:DerivativesMember
1719 Gross Derivatives Member wbk:GrossDerivativesMember
1720 Interest rate contracts Member wbk:IfrsInterestRateContractMember
1721 Interest rate contracts - Futures contracts Member ifrs-full:FuturesContractMember
1722 Interest rate contracts - Forward agreements Member wbk:InterestRateForwardAgreementsMember
1723 Interest rate contracts - Swap agreements Member ifrs-full:InterestRateSwapContractMember
1724 Interest rate contracts - Options Member wbk:InterestRateOptionContractsMember
1725 Foreign exchange contracts Member wbk:IfrsForeignExchangeContractMember
1726 Foreign exchange contracts - Spot and forward contracts Member wbk:ForeignExchangeSpotAndForwardContractsMember
1727 Foreign exchange contracts - Cross currency swap agreements Member ifrs-full:CurrencySwapContractMember
1728 Foreign exchange contracts - Options Member wbk:IfrsForeignExchangeOptionMember
1729 Commodity contracts Member wbk:IfrsCommodityContractMember
1730 Equities Member wbk:IfrsEquityContractMember
1731 Credit default swaps Member wbk:IfrsCreditDefaultSwapMember
1732 Impact of netting arrangements Member wbk:DerivativesNettingArrangementMember
1733 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
1734 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
1735 Parent Entity Member us-gaap:ParentCompanyMember
1736 Financial instruments LineItems ifrs-full:DisclosureOfFinancialInstrumentsLineItems
1737 Notional Amount Concept (Monetary) As Of ifrs-full:NotionalAmount
1738 Fair Value, Trading, Assets Concept (Monetary) As Of Debit ifrs-full:DerivativeFinancialAssetsHeldForTrading
1739 Fair Value, Trading, Liabilities Concept (Monetary) As Of Credit ifrs-full:DerivativeFinancialLiabilitiesHeldForTrading
1740 Fair Value, Hedging, Assets Concept (Monetary) As Of Debit ifrs-full:DerivativeFinancialAssetsHeldForHedging
1741 Fair Value, Hedging, Liabilities Concept (Monetary) As Of Credit ifrs-full:DerivativeFinancialLiabilitiesHeldForHedging
1742 Fair Value, Total, Assets Concept (Monetary) As Of Debit ifrs-full:DerivativeFinancialAssets
1743 Fair Value, Total, Liabilities Concept (Monetary) As Of Credit ifrs-full:DerivativeFinancialLiabilities
1744 42103 - Disclosure - Derivative financial instruments - Credit default swaps (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureDerivativeFinancialInstrumentsCreditDefaultSwapsDetails
1745 Disclosure of detailed information about financial instruments [table] Table

*

*

 ifrs-full:DisclosureOfFinancialInstrumentsTable
1746 Classes of financial instruments [axis] Axis ifrs-full:ClassesOfFinancialInstrumentsAxis
1747 Financial instruments, class [member] Member ifrs-full:ClassesOfFinancialInstrumentsMember
1748 Credit default swaps Member wbk:IfrsCreditDefaultSwapMember
1749 Credit protection bought Member wbk:CreditProtectionBoughtMember
1750 Credit protection sold Member wbk:CreditProtectionSoldMember
1751 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
1752 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
1753 Parent Entity Member us-gaap:ParentCompanyMember
1754 Financial instruments LineItems ifrs-full:DisclosureOfFinancialInstrumentsLineItems
1755 Notional Amount Concept (Monetary) As Of ifrs-full:NotionalAmount
1756 Fair Value, Total, Assets Concept (Monetary) As Of Debit ifrs-full:DerivativeFinancialAssets
1757 Fair Value, Total, Liabilities Concept (Monetary) As Of Credit ifrs-full:DerivativeFinancialLiabilities
1758 42201 - Disclosure - Financial risk - Credit risk (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureFinancialRiskCreditRiskDetails
1759 Disclosure of financial assets [table] Table

*

*

 ifrs-full:DisclosureOfFinancialAssetsTable
1760 Classes of financial assets [axis] Axis ifrs-full:ClassesOfFinancialAssetsAxis
1761 Financial assets Member ifrs-full:FinancialAssetsMember
1762 Trading securities and financial assets designated at fair value Member wbk:TradingSecuritiesAndFinancialAssetsDesignatedAtFairValueMember
1763 Available-for-sale securities Member wbk:IfrsAvailableForSaleSecuritiesMember
1764 Derivative financial instruments Member wbk:DerivativeFinancialAssetsMember
1765 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
1766 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
1767 Parent Entity Member us-gaap:ParentCompanyMember
1768 Financial assets LineItems ifrs-full:DisclosureOfFinancialAssetsLineItems
1769 Fair value related to credit risk Abstract ifrs-full:DisclosureOfCreditRiskExposureAbstract
1770 Financial assets issued by financial institutions (as a percent) Concept (Percent) As Of wbk:PercentageOfCreditConcentrationsFinancialAssetsIssuedByFinancialInstitutions
1771 Financial assets issued by government or semi-government authorities (as a percent) Concept (Percent) As Of wbk:PercentageOfCreditConcentrationsFinancialAssetsIssuedByGovernmentOrSemiGovernmentAuthorities
1772 Financial assets held in Australia (as a percent) Concept (Percent) As Of wbk:PercentageOfCreditConcentrationsFinancialAssetsHeldInAustralia
1773 42202 - Disclosure - Financial risk - Credit risk by industry (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureFinancialRiskCreditRiskByIndustryDetails
1774 Disclosure of credit risk exposure [table] Table

*

*

 ifrs-full:DisclosureOfCreditRiskExposureTable
1775 IFRS Industry of Counterparty, Type [Axis] Axis wbk:IfrsIndustryOfCounterpartyTypeAxis
1776 IFRS Industry of Counterparty [Domain] Member wbk:IfrsIndustryOfCounterpartyDomain
1777 Accommodation, cafes and restaurants Member wbk:AccommodationCafesAndRestaurantsMember
1778 Agriculture, forestry and fishing Member wbk:AgricultureForestryAndFishingMember
1779 Construction Member wbk:ConstructionMember
1780 Finance and insurance Member wbk:FinanceAndInsuranceMember
1781 Government, administration and defence Member wbk:GovernmentAdministrationAndDefenceMember
1782 Manufacturing Member wbk:ManufacturingMember
1783 Mining Member wbk:MiningMember
1784 Property Member wbk:PropertyMember
1785 Property services and business services Member wbk:PropertyServicesAndBusinessServicesMember
1786 Services Member wbk:ServicesMember
1787 Trade Member wbk:TradeMember
1788 Transport and storage Member wbk:TransportAndStorageMember
1789 Utilities Member wbk:UtilitiesMember
1790 Retail lending Member wbk:RetailLendingMember
1791 Other Member wbk:OtherIndustryMember
1792 Geographical areas [axis] Axis ifrs-full:GeographicalAreasAxis
1793 Geographical areas [member] Member ifrs-full:GeographicalAreasMember
1794 Australia Member country:AU
1795 New Zealand Member country:NZ
1796 Other Overseas Member wbk:OtherOverseasMember
1797 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
1798 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
1799 Parent Entity Member us-gaap:ParentCompanyMember
1800 Financial risk LineItems ifrs-full:DisclosureOfCreditRiskExposureLineItems
1801 Total on balance sheet Concept (Monetary) As Of Debit wbk:FinancialAssetsExposureToCreditRisk
1802 Undrawn credit commitments Concept (Monetary) As Of Credit wbk:UndrawnCreditCommitments
1803 Total gross credit risk Concept (Monetary) As Of ifrs-full:MaximumExposureToCreditRisk
1804 42203 - Disclosure - Financial risk - Credit quality of financial assets (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureFinancialRiskCreditQualityOfFinancialAssetsDetails
1805 Disclosure of credit risk exposure [table] Table

*

*

 ifrs-full:DisclosureOfCreditRiskExposureTable
1806 Types of risks [axis] Axis ifrs-full:TypesOfRisksAxis
1807 Risks [member] Member ifrs-full:TypesOfRisksMember
1808 Credit risk Member ifrs-full:CreditRiskMember
1809 Classes of financial assets [axis] Axis ifrs-full:ClassesOfFinancialAssetsAxis
1810 Financial assets Member ifrs-full:FinancialAssetsMember
1811 Receivables due from other financial institutions Member wbk:ReceivablesDueFromOtherFinancialInstitutionsMember
1812 Trading securities and financial assets designated at fair value Member wbk:TradingSecuritiesAndFinancialAssetsDesignatedAtFairValueMember
1813 Derivative financial instruments Member wbk:DerivativeFinancialAssetsMember
1814 Available-for-sale securities Member wbk:IfrsAvailableForSaleSecuritiesMember
1815 Loans Member wbk:LoansAndFinanceLeasesReceivableMember
1816 Loans - housing and personal Member ifrs-full:ConsumerLoansMember
1817 Loans - business Member ifrs-full:CorporateLoansMember
1818 Regulatory deposits with central banks overseas Member wbk:MandatoryReserveDepositsAtCentralBanksMember
1819 Due from subsidiaries Member wbk:DueFromSubsidiariesMember
1820 Other financial assets Member wbk:OtherFinancialAssetsMember
1821 Carrying amount, accumulated depreciation, amortisation and impairment and gross carrying amount [axis] Axis ifrs-full:CarryingAmountAccumulatedDepreciationAmortisationAndImpairmentAndGrossCarryingAmountAxis
1822 Carrying amount [member] Member ifrs-full:CarryingAmountMember
1823 Gross/Cost Member ifrs-full:GrossCarryingAmountMember
1824 Provision for impairment charges on loans Member ifrs-full:AllowanceForCreditLossesMember
1825 Impairment of financial assets [axis] Axis ifrs-full:ImpairmentOfFinancialAssetsAxis
1826 Entity's total for impairment of financial assets [member] Member ifrs-full:EntitysTotalForImpairmentOfFinancialAssetsMember
1827 Neither past due nor impaired Member ifrs-full:FinancialAssetsNeitherPastDueNorImpairedMember
1828 Past due but not impaired Member ifrs-full:FinancialAssetsPastDueButNotImpairedMember
1829 Impaired Member ifrs-full:FinancialAssetsImpairedMember
1830 Internal credit grades [axis] Axis ifrs-full:InternalCreditGradesAxis
1831 Entity's total for internal credit grades [member] Member ifrs-full:EntitysTotalForInternalCreditGradesMember
1832 Strong Member wbk:StrongCreditGradeMember
1833 Good/Satisfactory Member wbk:GoodOrSatisfactoryCreditGradeMember
1834 Weak Member wbk:WeakCreditGradeMember
1835 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
1836 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
1837 Parent Entity Member us-gaap:ParentCompanyMember
1838 Financial risk LineItems ifrs-full:DisclosureOfCreditRiskExposureLineItems
1839 Financial assets Concept (Monetary) As Of Debit ifrs-full:FinancialAssets
1840 Accrued interest Concept (Monetary) For Period Credit ifrs-full:InterestIncomeOnImpairedFinancialAssetsAccrued
1841 Securities sold not yet delivered Concept (Monetary) As Of Debit wbk:SecuritiesSoldButNotYetDeliveredIncludedInTradingSecurities
1842 42204 - Disclosure - Financial risk - Financial assets past due, but not impaired (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureFinancialRiskFinancialAssetsPastDueButNotImpairedDetails
1843 Disclosure of financial assets that are either past due or impaired [table] Table

*

*

 ifrs-full:DisclosureOfFinancialAssetsThatAreEitherPastDueOrImpairedTable
1844 Types of risks [axis] Axis ifrs-full:TypesOfRisksAxis
1845 Risks [member] Member ifrs-full:TypesOfRisksMember
1846 Credit risk Member ifrs-full:CreditRiskMember
1847 Carrying amount, accumulated depreciation, amortisation and impairment and gross carrying amount [axis] Axis ifrs-full:CarryingAmountAccumulatedDepreciationAmortisationAndImpairmentAndGrossCarryingAmountAxis
1848 Carrying amount [member] Member ifrs-full:CarryingAmountMember
1849 Gross/Cost Member ifrs-full:GrossCarryingAmountMember
1850 Impairment of financial assets [axis] Axis ifrs-full:ImpairmentOfFinancialAssetsAxis
1851 Entity's total for impairment of financial assets [member] Member ifrs-full:EntitysTotalForImpairmentOfFinancialAssetsMember
1852 Past due but not impaired Member ifrs-full:FinancialAssetsPastDueButNotImpairedMember
1853 Classes of financial assets [axis] Axis ifrs-full:ClassesOfFinancialAssetsAxis
1854 Financial assets Member ifrs-full:FinancialAssetsMember
1855 Loans Member wbk:LoansAndFinanceLeasesReceivableMember
1856 Loans - housing and personal Member ifrs-full:ConsumerLoansMember
1857 Loans - business Member ifrs-full:CorporateLoansMember
1858 Other financial assets Member wbk:OtherFinancialAssetsMember
1859 Past due status [axis] Axis ifrs-full:PastDueStatusAxis
1860 Past due status [member] Member ifrs-full:PastDueStatusMember
1861 1-5 days Member wbk:OneToFiveDaysMember
1862 6-89 days Member wbk:SixthToEightyNinthDayMember
1863 90+ days Member ifrs-full:LaterThanThreeMonthsMember
1864 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
1865 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
1866 Parent Entity Member us-gaap:ParentCompanyMember
1867 Past due receivables LineItems ifrs-full:DisclosureOfFinancialAssetsThatAreEitherPastDueOrImpairedLineItems
1868 Financial assets Concept (Monetary) As Of Debit ifrs-full:FinancialAssets
1869 42205 - Disclosure - Financial risk - Financial assets in default, but not impaired (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureFinancialRiskFinancialAssetsInDefaultButNotImpairedDetails
1870 Disclosure of financial assets that are either past due or impaired [table] Table

*

*

 ifrs-full:DisclosureOfFinancialAssetsThatAreEitherPastDueOrImpairedTable
1871 Types of risks [axis] Axis ifrs-full:TypesOfRisksAxis
1872 Risks [member] Member ifrs-full:TypesOfRisksMember
1873 Credit risk Member ifrs-full:CreditRiskMember
1874 Impairment of financial assets [axis] Axis ifrs-full:ImpairmentOfFinancialAssetsAxis
1875 Entity's total for impairment of financial assets [member] Member ifrs-full:EntitysTotalForImpairmentOfFinancialAssetsMember
1876 90 days past due or otherwise in default, not impaired Member wbk:FinancialAssets90DaysPastDueOrInDefaultNotImpairedMember
1877 Carrying amount, accumulated depreciation, amortisation and impairment and gross carrying amount [axis] Axis ifrs-full:CarryingAmountAccumulatedDepreciationAmortisationAndImpairmentAndGrossCarryingAmountAxis
1878 Carrying amount [member] Member ifrs-full:CarryingAmountMember
1879 Gross/Cost Member ifrs-full:GrossCarryingAmountMember
1880 Geographical areas [axis] Axis ifrs-full:GeographicalAreasAxis
1881 Geographical areas [member] Member ifrs-full:GeographicalAreasMember
1882 Australia Member country:AU
1883 New Zealand Member country:NZ
1884 Other Overseas Member wbk:OtherOverseasMember
1885 Past due receivables LineItems ifrs-full:DisclosureOfFinancialAssetsThatAreEitherPastDueOrImpairedLineItems
1886 Financial assets Concept (Monetary) As Of Debit ifrs-full:FinancialAssets
1887 42206 - Disclosure - Financial risk - Impaired loans (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureFinancialRiskImpairedLoansDetails
1888 Disclosure of financial assets that are either past due or impaired [table] Table

*

*

 ifrs-full:DisclosureOfFinancialAssetsThatAreEitherPastDueOrImpairedTable
1889 Types of risks [axis] Axis ifrs-full:TypesOfRisksAxis
1890 Risks [member] Member ifrs-full:TypesOfRisksMember
1891 Credit risk Member ifrs-full:CreditRiskMember
1892 Classes of financial assets [axis] Axis ifrs-full:ClassesOfFinancialAssetsAxis
1893 Financial assets Member ifrs-full:FinancialAssetsMember
1894 Loans Member wbk:LoansAndFinanceLeasesReceivableMember
1895 Loans - housing and personal Member ifrs-full:ConsumerLoansMember
1896 Loans - business Member ifrs-full:CorporateLoansMember
1897 Impairment of financial assets [axis] Axis ifrs-full:ImpairmentOfFinancialAssetsAxis
1898 Entity's total for impairment of financial assets [member] Member ifrs-full:EntitysTotalForImpairmentOfFinancialAssetsMember
1899 Impaired Member ifrs-full:FinancialAssetsImpairedMember
1900 Individually impaired Member ifrs-full:FinancialAssetsIndividuallyAssessedForCreditLossesMember
1901 Collectively impaired Member ifrs-full:FinancialAssetsCollectivelyAssessedForCreditLossesMember
1902 Carrying amount, accumulated depreciation, amortisation and impairment and gross carrying amount [axis] Axis ifrs-full:CarryingAmountAccumulatedDepreciationAmortisationAndImpairmentAndGrossCarryingAmountAxis
1903 Carrying amount [member] Member ifrs-full:CarryingAmountMember
1904 Gross/Cost Member ifrs-full:GrossCarryingAmountMember
1905 Provision for impairment charges on loans Member ifrs-full:AllowanceForCreditLossesMember
1906 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
1907 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
1908 Parent Entity Member us-gaap:ParentCompanyMember
1909 Past due receivables LineItems ifrs-full:DisclosureOfFinancialAssetsThatAreEitherPastDueOrImpairedLineItems
1910 Financial assets Concept (Monetary) As Of Debit ifrs-full:FinancialAssets
1911 42207 - Disclosure - Financial risk - Impaired loans by type and geography (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureFinancialRiskImpairedLoansByTypeAndGeographyDetails
1912 Disclosure of financial assets that are either past due or impaired [table] Table

*

*

 ifrs-full:DisclosureOfFinancialAssetsThatAreEitherPastDueOrImpairedTable
1913 Types of risks [axis] Axis ifrs-full:TypesOfRisksAxis
1914 Risks [member] Member ifrs-full:TypesOfRisksMember
1915 Credit risk Member ifrs-full:CreditRiskMember
1916 Impairment of financial assets [axis] Axis ifrs-full:ImpairmentOfFinancialAssetsAxis
1917 Entity's total for impairment of financial assets [member] Member ifrs-full:EntitysTotalForImpairmentOfFinancialAssetsMember
1918 Impaired Member ifrs-full:FinancialAssetsImpairedMember
1919 Classes of financial assets [axis] Axis ifrs-full:ClassesOfFinancialAssetsAxis
1920 Financial assets Member ifrs-full:FinancialAssetsMember
1921 Loans Member wbk:LoansAndFinanceLeasesReceivableMember
1922 Geographical areas [axis] Axis ifrs-full:GeographicalAreasAxis
1923 Geographical areas [member] Member ifrs-full:GeographicalAreasMember
1924 Australia Member country:AU
1925 New Zealand Member country:NZ
1926 Other Overseas Member wbk:OtherOverseasMember
1927 Credit impairment of financial instruments [axis] Axis ifrs-full:CreditImpairmentOfFinancialInstrumentsAxis
1928 Credit impairment of financial instruments [member] Member ifrs-full:CreditImpairmentOfFinancialInstrumentsMember
1929 Non-performing loans Member wbk:NonPerformingLoansMember
1930 Restructured loans Member wbk:RestructuredLoansMember
1931 Overdrafts, personal loans and revolving credit facilities greater than 90 days past due Member wbk:OverdraftsPersonalAndRevolvingCreditFacilitiesDueForMoreThanThreeMonthsMember
1932 Carrying amount, accumulated depreciation, amortisation and impairment and gross carrying amount [axis] Axis ifrs-full:CarryingAmountAccumulatedDepreciationAmortisationAndImpairmentAndGrossCarryingAmountAxis
1933 Carrying amount [member] Member ifrs-full:CarryingAmountMember
1934 Gross/Cost Member ifrs-full:GrossCarryingAmountMember
1935 Provision for impairment charges on loans Member ifrs-full:AllowanceForCreditLossesMember
1936 Past due receivables LineItems ifrs-full:DisclosureOfFinancialAssetsThatAreEitherPastDueOrImpairedLineItems
1937 Financial assets Concept (Monetary) As Of Debit ifrs-full:FinancialAssets
1938 42208 - Disclosure - Financial risk - Interest on non-performing loans and restructured financial assets (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureFinancialRiskInterestOnNonPerformingLoansAndRestructuredFinancialAssetsDetails
1939 Disclosure of financial assets that are either past due or impaired [table] Table

*

*

 ifrs-full:DisclosureOfFinancialAssetsThatAreEitherPastDueOrImpairedTable
1940 Geographical areas [axis] Axis ifrs-full:GeographicalAreasAxis
1941 Geographical areas [member] Member ifrs-full:GeographicalAreasMember
1942 Australia Member country:AU
1943 Overseas Member wbk:OverseasMember
1944 Past due receivables LineItems ifrs-full:DisclosureOfFinancialAssetsThatAreEitherPastDueOrImpairedLineItems
1945 Interest received Concept (Monetary) For Period Credit wbk:InterestReceivedOnNonPerformingLoansAndRestructuredFinancialAssets
1946 Interest forgone Concept (Monetary) For Period Debit wbk:InterestForgoneOnNonPerformingLoansAndRestructuredFinancialAssets
1947 42209 - Disclosure - Financial risk - Coverage from collateral held (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureFinancialRiskCoverageFromCollateralHeldDetails
1948 Disclosure of financial assets [table] Table

*

*

 ifrs-full:DisclosureOfFinancialAssetsTable
1949 Impairment of financial assets [axis] Axis ifrs-full:ImpairmentOfFinancialAssetsAxis
1950 Entity's total for impairment of financial assets [member] Member ifrs-full:EntitysTotalForImpairmentOfFinancialAssetsMember
1951 Neither past due nor impaired Member ifrs-full:FinancialAssetsNeitherPastDueNorImpairedMember
1952 Past due but not impaired Member ifrs-full:FinancialAssetsPastDueButNotImpairedMember
1953 Impaired Member ifrs-full:FinancialAssetsImpairedMember
1954 Classes of financial assets [axis] Axis ifrs-full:ClassesOfFinancialAssetsAxis
1955 Financial assets Member ifrs-full:FinancialAssetsMember
1956 Loans - housing and personal Member ifrs-full:ConsumerLoansMember
1957 Loans - business Member ifrs-full:CorporateLoansMember
1958 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
1959 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
1960 Parent Entity Member us-gaap:ParentCompanyMember
1961 Financial assets LineItems ifrs-full:DisclosureOfFinancialAssetsLineItems
1962 Loan portfolio, coverage from collateral held Abstract wbk:LoansAndReceivablesCoverageFromCollateralAbstract
1963 Fully secured (as a percent) Concept (Percent) As Of wbk:PercentageOfCoverageFromCollateralHeldFullySecured
1964 Partially secured (as a percent) Concept (Percent) As Of wbk:PercentageOfCoverageFromCollateralHeldPartiallySecured
1965 Unsecured (as a percent) Concept (Percent) As Of wbk:PercentageOfCoverageFromCollateralHeldUnsecured
1966 Total (as a percentage) Concept (Percent) As Of wbk:TotalPercentageOfLoanPortfolio
1967 42210 - Disclosure - Financial risk - Collateral held against financial assets other than loans (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureFinancialRiskCollateralHeldAgainstFinancialAssetsOtherThanLoansDetails
1968 Disclosure of financial assets [table] Table

*

*

 ifrs-full:DisclosureOfFinancialAssetsTable
1969 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
1970 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
1971 Parent Entity Member us-gaap:ParentCompanyMember
1972 Financial assets LineItems ifrs-full:DisclosureOfFinancialAssetsLineItems
1973 Cash primarily for derivatives Concept (Monetary) As Of Debit wbk:CashPrimarilyForDerivativesOtherCollateral
1974 Securities under reverse repurchase agreement Concept (Monetary) As Of Debit wbk:SecuritiesUnderReverseRepurchaseAgreementOtherCollateral
1975 Securities under derivatives and stock borrowing Concept (Monetary) As Of Debit wbk:SecuritiesUnderDerivativesAndStockBorrowingOtherCollateral
1976 Total other collateral held Concept (Monetary) As Of Debit wbk:CollateralHeldAgainstFinancialAssetsOtherThanLoansTotal
1977 42211 - Disclosure - Financial risk - Liquid assets (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureFinancialRiskLiquidAssetsDetails
1978 Disclosure of financial assets [table] Table

*

*

 ifrs-full:DisclosureOfFinancialAssetsTable
1979 Range [axis] Axis ifrs-full:RangeAxis
1980 Ranges [member] Member ifrs-full:RangesMember
1981 Average Member ifrs-full:WeightedAverageMember
1982 Types of risks [axis] Axis ifrs-full:TypesOfRisksAxis
1983 Risks [member] Member ifrs-full:TypesOfRisksMember
1984 Liquidity risk Member ifrs-full:LiquidityRiskMember
1985 Classes of financial assets [axis] Axis ifrs-full:ClassesOfFinancialAssetsAxis
1986 Financial assets Member ifrs-full:FinancialAssetsMember
1987 Cash Member wbk:IfrsCashMember
1988 Receivables due from other financial institutions Member wbk:ReceivablesDueFromOtherFinancialInstitutionsMember
1989 Trading securities and financial assets designated at fair value Member wbk:TradingSecuritiesAndFinancialAssetsDesignatedAtFairValueMember
1990 Available-for-sale securities Member wbk:IfrsAvailableForSaleSecuritiesMember
1991 Loans Member wbk:IfrsLoansReceivableMember
1992 Regulatory deposits with central banks overseas Member wbk:MandatoryReserveDepositsAtCentralBanksMember
1993 Financial assets LineItems ifrs-full:DisclosureOfFinancialAssetsLineItems
1994 Increase (decrease) in liquid assets Concept (Monetary) For Period Debit wbk:IncreaseDecreaseInLiquidAssets
1995 Liquid assets Concept (Monetary) As Of Debit ifrs-full:FinancialAssetsHeldForManagingLiquidityRisk
1996 42212 - Disclosure - Financial risk - Funding composition (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureFinancialRiskFundingCompositionDetails
1997 Disclosure of nature and extent of risks arising from financial instruments [table] Table

*

*

 ifrs-full:DisclosureOfNatureAndExtentOfRisksArisingFromFinancialInstrumentsTable
1998 Maturity [axis] Axis ifrs-full:MaturityAxis
1999 Aggregated time bands [member] Member ifrs-full:AggregatedTimeBandsMember
2000 Over 1 Year Member ifrs-full:LaterThanOneYearMember
2001 No later than one year Member ifrs-full:NotLaterThanOneYearMember
2002 Financial risk LineItems ifrs-full:DisclosureOfNatureAndExtentOfRisksArisingFromFinancialInstrumentsLineItems
2003 Group's total funding Abstract wbk:TotalFundingAbstract
2004 Customer deposits Concept (Percent) As Of wbk:PercentageOfFundingThroughCustomerDeposits
2005 Wholesale term funding with residual maturity Concept (Percent) As Of wbk:PercentageOfFundingThroughWholesaleTermFunding
2006 Securitisation Concept (Percent) As Of wbk:PercentageOfFundingThroughSecuritisation
2007 Equity Concept (Percent) As Of wbk:PercentageOfFundingThroughEquity
2008 Group's total funding Concept (Percent) As Of wbk:PercentageOfTotalFunding
2009 Movements in the Group's funding composition Abstract wbk:MovementsInGroupsFundingCompositionAbstract
2010 Increase in funding through customer deposits Concept (Percent) For Period wbk:IncreaseDecreaseInPercentageOfFundingThroughCustomerDeposits
2011 Increase (decrease) in funding through wholesale term funding Concept (Percent) For Period wbk:IncreaseDecreaseInPercentageOfFundingThroughWholesaleTermFunding
2012 Short term funding portfolio (in AUD) Concept (Monetary) As Of Credit wbk:ShortTermFundingPortfolio
2013 Weighted average maturity period for short term funding portfolio Concept (xbrli:durationItemType) For Period wbk:WeightedAverageMaturityPeriodForShortTermFundingPortfolio
2014 Unencumbered repo-eligible liquid assets and cash (in AUD) Concept (Monetary) As Of Debit wbk:RepoEligibleLiquidAssetsAndCash
2015 Long term wholesale funding raised (in AUD) Concept (Monetary) For Period Credit wbk:LongTermWholesaleFundingRaised
2016 Basel III compliant Additional Tier 1 and Tier 2 capital in long term wholesale funding (in AUD) Concept (Monetary) As Of Credit wbk:LongTermWholesaleFundingOfBaselIiiCompliantAdditionalTierOneAndTierTwoCapital
2017 42213 - Disclosure - Financial risk - Assets pledged as collateral (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureFinancialRiskAssetsPledgedAsCollateralDetails
2018 Disclosure of financial assets [table] Table

*

*

 ifrs-full:DisclosureOfFinancialAssetsTable
2019 Classes of financial assets [axis] Axis ifrs-full:ClassesOfFinancialAssetsAxis
2020 Financial assets Member ifrs-full:FinancialAssetsMember
2021 Cash Member wbk:IfrsCashMember
2022 Cash Deposit on Stock Borrowed Member wbk:CashDepositOnStockBorrowedMember
2023 Securities (including certificates of deposit) Member wbk:SecuritiesIncludingCertificatesOfDepositMember
2024 Securities pledged under repurchase agreements Member wbk:SecuritiesPledgedUnderRepurchaseAgreementsMember
2025 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
2026 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
2027 Parent Entity Member us-gaap:ParentCompanyMember
2028 Financial assets LineItems ifrs-full:DisclosureOfFinancialAssetsLineItems
2029 Amount pledged to secure liabilities Concept (Monetary) As Of Debit ifrs-full:FinancialAssetsPledgedAsCollateralForLiabilitiesOrContingentLiabilities
2030 42214 - Disclosure - Financial risk - Contractual maturity of financial liabilities (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureFinancialRiskContractualMaturityOfFinancialLiabilitiesDetails
2031 Disclosure of maturity analysis for derivative financial liabilities [table] Table

*

*

 ifrs-full:DisclosureOfMaturityAnalysisForDerivativeFinancialLiabilitiesTable
2032 Classes of financial liabilities [axis] Axis ifrs-full:ClassesOfFinancialLiabilitiesAxis
2033 Financial liabilities, class [member] Member ifrs-full:FinancialLiabilitiesMember
2034 Total financial liabilities excluding loan capital Member wbk:FinancialLiabilitiesExcludingLoanCapitalMember
2035 Payables due to other financial institutions Member wbk:PayablesDueToOtherFinancialInstitutionMember
2036 Deposits and other borrowings Member wbk:DepositsAndOtherBorrowingMember
2037 Other financial liabilities at fair value through income statement Member wbk:OtherFinancialLiabilitiesAtFairValueThroughProfitOrLossMember
2038 Derivative financial instruments: Held for trading Member wbk:DerivativeFinancialLiabilitiesHeldForTradingMember
2039 Derivative financial instruments: Held for hedging purposes (net settled) Member wbk:DerivativeFinancialLiabilitiesHeldForHedgingNetSettledMember
2040 Derivative financial instruments: Held for hedging purposes (gross settled) Member wbk:DerivativeFinancialLiabilitiesHeldForHedgingGrossSettledMember
2041 Debt issues Member wbk:DebtIssuesMember
2042 Due to subsidiaries Member wbk:DueToSubsidiariesMember
2043 Other financial liabilities Member wbk:OtherFinancialLiabilitiesMember
2044 Loan capital Member wbk:LoanForCapitalMember
2045 Letters of credit and guarantees Member wbk:LettersOfCreditAndGuaranteesMember
2046 Commitments to extend credit Member wbk:CommitmentsToExtendCreditsMember
2047 Other commitments Member wbk:OtherCommitmentsMember
2048 Maturity [axis] Axis ifrs-full:MaturityAxis
2049 Aggregated time bands [member] Member ifrs-full:AggregatedTimeBandsMember
2050 Less than or Up to 1 Month Member ifrs-full:NotLaterThanOneMonthMember
2051 Over 1 Month to 3 Months Member ifrs-full:LaterThanOneMonthAndNotLaterThanThreeMonthsMember
2052 Over 3 Months to 1 Year Member ifrs-full:LaterThanThreeMonthsAndNotLaterThanOneYearMember
2053 Over 1 Year to 5 Years Member ifrs-full:LaterThanOneYearAndNotLaterThanFiveYearsMember
2054 Over 5 Years Member ifrs-full:LaterThanFiveYearsMember
2055 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
2056 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
2057 Parent Entity Member us-gaap:ParentCompanyMember
2058 Disclosure of maturity analysis for derivative financial liabilities [line items] LineItems ifrs-full:DisclosureOfMaturityAnalysisForDerivativeFinancialLiabilitiesLineItems
2059 Disclosure of financial liabilities [abstract] Abstract ifrs-full:DisclosureOfFinancialLiabilitiesAbstract
2060 Non-derivative financial instruments: Concept (Monetary) As Of Credit ifrs-full:NonderivativeFinancialLiabilitiesUndiscountedCashFlows
2061 Derivative financial instruments Concept (Monetary) As Of Credit ifrs-full:DerivativeFinancialLiabilitiesUndiscountedCashFlows
2062 Derivative financial instruments: Cash outflow Concept (Monetary) As Of Credit wbk:DerivativeFinancialLiabilitiesUndiscountedCashOutflows
2063 Derivative financial instruments: Cash inflow Concept (Monetary) As Of Debit wbk:DerivativeFinancialLiabilitiesUndiscountedCashInflows
2064 Total undiscounted financial liabilities Concept (Monetary) As Of Credit wbk:FinancialLiabilitiesUndiscountedCashFlows
2065 Total undiscounted contingent liabilities and commitments Concept (Monetary) As Of Credit wbk:ContingentLiabilitiesAndCommitmentsUndiscountedCashFlows
2066 42215 - Disclosure - Financial risk - Expected maturity of financial assets and financial liabilities (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureFinancialRiskExpectedMaturityOfFinancialAssetsAndFinancialLiabilitiesDetails
2067 Disclosure of amounts to be recovered or settled after twelve months for classes of assets and liabilities that contain amounts to be recovered or settled both no more and more than twelve months after reporting date [table] Table

*

*

 ifrs-full:DisclosureOfAmountsToBeRecoveredOrSettledAfterTwelveMonthsForClassesOfAssetsAndLiabilitiesThatContainAmountsToBeRecoveredOrSettledBothNoMoreAndMoreThanTwelveMonthsAfterReportingDateTable
2068 Maturity [axis] Axis ifrs-full:MaturityAxis
2069 Aggregated time bands [member] Member ifrs-full:AggregatedTimeBandsMember
2070 No later than one year Member ifrs-full:NotLaterThanOneYearMember
2071 Over 1 Year Member ifrs-full:LaterThanOneYearMember
2072 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
2073 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
2074 Parent Entity Member us-gaap:ParentCompanyMember
2075 Disclosure of amounts to be recovered or settled after twelve months for classes of assets and liabilities that contain amounts to be recovered or settled both no more and more than twelve months after reporting date [line items] LineItems ifrs-full:DisclosureOfAmountsToBeRecoveredOrSettledAfterTwelveMonthsForClassesOfAssetsAndLiabilitiesThatContainAmountsToBeRecoveredOrSettledBothNoMoreAndMoreThanTwelveMonthsAfterReportingDateLineItems
2076 Assets Abstract ifrs-full:AssetsAbstract
2077 Cash and balances with central banks Concept (Monetary) As Of Debit ifrs-full:CashAndBankBalancesAtCentralBanks
2078 Receivables due from other financial institutions Concept (Monetary) As Of Debit wbk:ReceivablesDueFromOtherFinancialInstitutions
2079 Trading securities and financial assets designated at fair value Concept (Monetary) As Of Debit ifrs-full:FinancialAssetsAtFairValueThroughProfitOrLoss
2080 Derivative financial instruments Concept (Monetary) As Of Debit ifrs-full:DerivativeFinancialAssets
2081 Available-for-sale securities Concept (Monetary) As Of Debit ifrs-full:FinancialAssetsAvailableforsale
2082 Loans (net of provisions) Concept (Monetary) As Of Debit ifrs-full:LoansAndReceivables
2083 Life insurance assets Concept (Monetary) As Of Debit wbk:LifeInsuranceAssets
2084 Regulatory deposits with central banks overseas Concept (Monetary) As Of Debit ifrs-full:MandatoryReserveDepositsAtCentralBanks
2085 Due from subsidiaries Concept (Monetary) As Of Debit ifrs-full:TradeAndOtherReceivablesDueFromRelatedParties
2086 Investments in associates Concept (Monetary) As Of Debit ifrs-full:InvestmentsInAssociates
2087 Investment in subsidiaries Concept (Monetary) As Of Debit ifrs-full:InvestmentsInSubsidiaries
2088 All other assets Concept (Monetary) As Of Debit wbk:AllOtherAssets
2089 Total assets Concept (Monetary) As Of Debit ifrs-full:Assets
2090 Liabilities [abstract] Abstract ifrs-full:LiabilitiesAbstract
2091 Payables due to other financial institutions Concept (Monetary) As Of Credit wbk:PayablesDueToOtherFinancialInstitutions
2092 Deposits and other borrowings Concept (Monetary) As Of Credit wbk:DepositsAndOtherBorrowings
2093 Other financial liabilities at fair value through income statement Concept (Monetary) As Of Credit ifrs-full:FinancialLiabilitiesAtFairValueThroughProfitOrLoss
2094 Derivative financial instruments Concept (Monetary) As Of Credit ifrs-full:DerivativeFinancialLiabilities
2095 Debt issues Concept (Monetary) As Of Credit ifrs-full:DebtSecurities
2096 Due to subsidiaries Concept (Monetary) As Of Credit ifrs-full:TradeAndOtherPayablesToRelatedParties
2097 Life insurance liabilities Concept (Monetary) As Of Credit ifrs-full:LiabilitiesArisingFromInsuranceContracts
2098 All other liabilities Concept (Monetary) As Of Credit wbk:AllOtherLiabilities
2099 Total liabilities excluding loan capital Concept (Monetary) As Of Credit wbk:LiabilitiesExcludingLoanCapital
2100 Loan capital Concept (Monetary) As Of Credit wbk:LoanCapital
2101 Total liabilities Concept (Monetary) As Of Credit ifrs-full:Liabilities
2102 Net assets/(net liabilities) Concept (Monetary) As Of Debit ifrs-full:NetAssetsLiabilities
2103 42216 - Disclosure - Financial risk - Value-at-Risk (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureFinancialRiskValueAtRiskDetails
2104 Implied Table Table

*

*

 implied:Table
2105 Financial risk Abstract wbk:FinancialRiskAbstract
2106 Key parameters of VaR Abstract wbk:KeyParametersOfVarAbstract
2107 Holding period Concept (xbrli:durationItemType) For Period wbk:HoldingPeriodForVar
2108 Confidence level Concept (Percent) For Period wbk:ConfidenceLevelForVar
2109 Period of historical data used Concept (xbrli:durationItemType) For Period wbk:PeriodOfHistoricalDataUsedForVar
2110 42217 - Disclosure - Financial risk - Traded market risk (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureFinancialRiskTradedMarketRiskDetails
2111 Disclosure of nature and extent of risks arising from financial instruments [table] Table

*

*

 ifrs-full:DisclosureOfNatureAndExtentOfRisksArisingFromFinancialInstrumentsTable
2112 Types of risks [axis] Axis ifrs-full:TypesOfRisksAxis
2113 Risks [member] Member ifrs-full:TypesOfRisksMember
2114 Net market risk Member ifrs-full:MarketRiskMember
2115 Interest rate risk Member ifrs-full:InterestRateRiskMember
2116 Foreign exchange risk Member ifrs-full:CurrencyRiskMember
2117 Equity risk Member ifrs-full:EquityPriceRiskMember
2118 Commodity risk Member ifrs-full:CommodityPriceRiskMember
2119 Other market risks Member wbk:OtherMarketRisksMember
2120 Diversification effect Member ifrs-full:RiskDiversificationEffectMember
2121 Range [axis] Axis ifrs-full:RangeAxis
2122 Ranges [member] Member ifrs-full:RangesMember
2123 Maximum Member ifrs-full:TopOfRangeMember
2124 Minimum Member ifrs-full:BottomOfRangeMember
2125 Average Member ifrs-full:WeightedAverageMember
2126 Disclosure of nature and extent of risks arising from financial instruments [line items] LineItems ifrs-full:DisclosureOfNatureAndExtentOfRisksArisingFromFinancialInstrumentsLineItems
2127 Traded market risk Abstract wbk:TradedMarketRiskAbstract
2128 Value at risk Concept (Monetary) As Of ifrs-full:ValueAtRisk
2129 42218 - Disclosure - Financial risk - Non-traded market risk (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureFinancialRiskNonTradedMarketRiskDetails
2130 Disclosure of nature and extent of risks arising from financial instruments [table] Table

*

*

 ifrs-full:DisclosureOfNatureAndExtentOfRisksArisingFromFinancialInstrumentsTable
2131 Range [axis] Axis ifrs-full:RangeAxis
2132 Ranges [member] Member ifrs-full:RangesMember
2133 Maximum Member ifrs-full:TopOfRangeMember
2134 Minimum Member ifrs-full:BottomOfRangeMember
2135 Average Member ifrs-full:WeightedAverageMember
2136 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
2137 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
2138 Parent Entity Member us-gaap:ParentCompanyMember
2139 Disclosure of nature and extent of risks arising from financial instruments [line items] LineItems ifrs-full:DisclosureOfNatureAndExtentOfRisksArisingFromFinancialInstrumentsLineItems
2140 Non-traded market risk Abstract wbk:NonTradedMarketRiskAbstract
2141 Time horizon for modelling of interest rate scenarios Concept (xbrli:durationItemType) For Period wbk:PeriodOfProjectionForNar
2142 Confidence level Concept (Percent) For Period wbk:ConfidenceLevelForNar
2143 Variance from current market yield used in modelling interest rate scenarios Concept (Percent) For Period wbk:VarianceFromCurrentMarketYieldForNar
2144 Net interest income-at-risk (NaR) Abstract wbk:NetInterestIncomeAtRiskAbstract
2145 Percentage NaR over reported net interest income Concept (Percent) As Of wbk:PercentageOfNetInterestIncomeAtRiskOverReportedNetIncome
2146 Value at Risk - IRRBB Abstract wbk:ValueAtRiskIrrbbAbstract
2147 Value at Risk - IRBBB Concept (Monetary) As Of Debit wbk:ValueAtRiskForInterestRateRiskInBankingBooks
2148 42301 - Disclosure - Fair values of financial assets and financial liabilities (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureFairValuesOfFinancialAssetsAndFinancialLiabilitiesDetails
2149 Disclosure of detailed information about financial instruments [table] Table

*

*

 ifrs-full:DisclosureOfFinancialInstrumentsTable
2150 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
2151 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
2152 Parent Entity Member us-gaap:ParentCompanyMember
2153 Measurement [axis] Axis ifrs-full:MeasurementAxis
2154 Aggregated measurement [member] Member ifrs-full:AggregatedMeasurementMember
2155 Recurring Member ifrs-full:RecurringFairValueMeasurementMember
2156 Classes of financial assets [axis] Axis ifrs-full:ClassesOfFinancialAssetsAxis
2157 Financial assets Member ifrs-full:FinancialAssetsMember
2158 Trading securities and financial assets designated at fair value Member wbk:TradingSecuritiesAndFinancialAssetsDesignatedAtFairValueMember
2159 Derivative financial instruments Member wbk:DerivativeFinancialAssetsMember
2160 Available-for-sale securities Member wbk:IfrsAvailableForSaleSecuritiesMember
2161 Loans Member wbk:LoansAndFinanceLeasesReceivableMember
2162 Life insurance assets Member wbk:LifeInsuranceAssetsMember
2163 Regulatory deposits with central banks overseas Member wbk:MandatoryReserveDepositsAtCentralBanksMember
2164 Classes of financial liabilities [axis] Axis ifrs-full:ClassesOfFinancialLiabilitiesAxis
2165 Financial liabilities, class [member] Member ifrs-full:FinancialLiabilitiesMember
2166 Deposits and other borrowings Member wbk:DepositsAndOtherBorrowingsMember
2167 Other financial liabilities at fair value through income statement Member wbk:OtherFinancialLiabilitiesAtFairValueThroughProfitOrLossMember
2168 Derivative financial instruments Member wbk:DerivativeFinancialLiabilitiesMember
2169 Debt issues Member wbk:DebtIssuesMember
2170 Life insurance liabilities Member wbk:LifeInsuranceLiabilitiesMember
2171 Levels of fair value hierarchy [axis] Axis ifrs-full:LevelsOfFairValueHierarchyAxis
2172 All levels of fair value hierarchy [member] Member ifrs-full:AllLevelsOfFairValueHierarchyMember
2173 Level 1 Member ifrs-full:Level1OfFairValueHierarchyMember
2174 Level 2 Member ifrs-full:Level2OfFairValueHierarchyMember
2175 Level 3 Member ifrs-full:Level3OfFairValueHierarchyMember
2176 Fair values of financial assets and financial liabilities LineItems ifrs-full:DisclosureOfFinancialInstrumentsLineItems
2177 Financial assets measured at fair value on a recurring basis Concept (Monetary) As Of Debit ifrs-full:FinancialAssetsAtFairValue
2178 Financial liabilities measured at fair value on a recurring basis Concept (Monetary) As Of Credit ifrs-full:FinancialLiabilitiesAtFairValue
2179 42302 - Disclosure - Fair values of financial assets and financial liabilities - Non-market observable valuation techniques Level 3 (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureFairValuesOfFinancialAssetsAndFinancialLiabilitiesNonMarketObservableValuationTechniquesLevel3Details
2180 Disclosure of detailed information about financial instruments [table] Table

*

*

 ifrs-full:DisclosureOfFinancialInstrumentsTable
2181 Measurement [axis] Axis ifrs-full:MeasurementAxis
2182 Aggregated measurement [member] Member ifrs-full:AggregatedMeasurementMember
2183 At fair value Member ifrs-full:AtFairValueMember
2184 Levels of fair value hierarchy [axis] Axis ifrs-full:LevelsOfFairValueHierarchyAxis
2185 All levels of fair value hierarchy [member] Member ifrs-full:AllLevelsOfFairValueHierarchyMember
2186 Level 3 Member ifrs-full:Level3OfFairValueHierarchyMember
2187 Classes of financial assets [axis] Axis ifrs-full:ClassesOfFinancialAssetsAxis
2188 Financial assets Member ifrs-full:FinancialAssetsMember
2189 Trading securities and financial assets designated at fair value Member wbk:TradingSecuritiesAndFinancialAssetsDesignatedAtFairValueMember
2190 Derivative financial instruments Member wbk:DerivativeFinancialAssetsMember
2191 Available-for-sale securities Member wbk:IfrsAvailableForSaleSecuritiesMember
2192 Classes of financial liabilities [axis] Axis ifrs-full:ClassesOfFinancialLiabilitiesAxis
2193 Financial liabilities, class [member] Member ifrs-full:FinancialLiabilitiesMember
2194 Derivative financial instruments Member wbk:DerivativeFinancialLiabilitiesMember
2195 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
2196 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
2197 Parent Entity Member us-gaap:ParentCompanyMember
2198 Fair values of financial assets and financial liabilities LineItems ifrs-full:DisclosureOfFinancialInstrumentsLineItems
2199 Total Level 3 Assets Abstract ifrs-full:ReconciliationOfChangesInFairValueMeasurementAssetsAbstract
2200 Balance as at beginning of year Concept (Monetary) As Of Debit ifrs-full:FinancialAssets
2201 Income statements Concept (Monetary) For Period ifrs-full:GainsLossesRecognisedInProfitOrLossFairValueMeasurementAssets
2202 Available-for-sale reserve Concept (Monetary) For Period ifrs-full:GainsLossesRecognisedInOtherComprehensiveIncomeFairValueMeasurementAssets
2203 Acquisition and issues Concept (Monetary) For Period Debit wbk:AcquisitionAndIssuesFairValueMeasurementAssets
2204 Disposal and settlements Concept (Monetary) For Period Credit wbk:DisposalAndSettlementsFairValueMeasurementAssets
2205 Transfer into or out of non-market observables Concept (Monetary) For Period Debit wbk:TransfersIntoAndOutOfLevel3OfFairValueHierarchyAssets
2206 Foreign currency translation impacts Concept (Monetary) For Period Debit wbk:ForeignCurrencyTranslationFairValueMeasurementAssets
2207 Balance as at end of year Concept (Monetary) As Of Debit ifrs-full:FinancialAssets
2208 Unrealised gains/(losses) recognised in the income statements for financial instruments held as at 30 September 2017 Concept (Monetary) For Period Credit ifrs-full:GainsLossesRecognisedInProfitOrLossAttributableToChangeInUnrealisedGainsOrLossesForAssetsHeldAtEndOfPeriodFairValueMeasurement
2209 Total Level 3 Liabilities Abstract ifrs-full:ReconciliationOfChangesInFairValueMeasurementLiabilitiesAbstract
2210 Balance as at beginning of year Concept (Monetary) As Of Credit ifrs-full:FinancialLiabilities
2211 Income statements Concept (Monetary) For Period ifrs-full:GainsLossesRecognisedInProfitOrLossFairValueMeasurementLiabilities
2212 Acquisition and issues Concept (Monetary) For Period Credit wbk:AcquisitionAndIssuesFairValueMeasurementLiabilities
2213 Disposal and settlements Concept (Monetary) For Period Debit wbk:DisposalAndSettlementsFairValueMeasurementLiabilities
2214 Transfer into or out of non-market observables Concept (Monetary) For Period Credit wbk:TransfersIntoAndOutOfLevel3OfFairValueHierarchyLiabilities
2215 Balance as at end of year Concept (Monetary) As Of Credit ifrs-full:FinancialLiabilities
2216 Unrealised gains/(losses) recognised in the income statements for financial instruments held as at 30 September 2017 Concept (Monetary) For Period Credit ifrs-full:GainsLossesRecognisedInProfitOrLossAttributableToChangeInUnrealisedGainsOrLossesForLiabilitiesHeldAtEndOfPeriodFairValueMeasurement
2217 Day one profit or loss Abstract wbk:DayOneProfitOrLossAbstract
2218 Closing balance of unrecognised day one profit Concept (Monetary) As Of Debit wbk:ClosingBalanceOfUnrecognisedDayOneProfit
2219 42303 - Disclosure - Fair values of financial assets and financial liabilities - Not measured at fair value (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureFairValuesOfFinancialAssetsAndFinancialLiabilitiesNotMeasuredAtFairValueDetails
2220 Disclosure of detailed information about financial instruments [table] Table

*

*

 ifrs-full:DisclosureOfFinancialInstrumentsTable
2221 Measurement [axis] Axis ifrs-full:MeasurementAxis
2222 Aggregated measurement [member] Member ifrs-full:AggregatedMeasurementMember
2223 Not measured at fair value Member ifrs-full:NotMeasuredAtFairValueInStatementOfFinancialPositionButForWhichFairValueIsDisclosedMember
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2225 All levels of fair value hierarchy [member] Member ifrs-full:AllLevelsOfFairValueHierarchyMember
2226 Level 1 Member ifrs-full:Level1OfFairValueHierarchyMember
2227 Level 2 Member ifrs-full:Level2OfFairValueHierarchyMember
2228 Level 3 Member ifrs-full:Level3OfFairValueHierarchyMember
2229 Classes of financial assets [axis] Axis ifrs-full:ClassesOfFinancialAssetsAxis
2230 Financial assets Member ifrs-full:FinancialAssetsMember
2231 Cash and balances with central banks Member wbk:CashAndBalancesWithCentralBanksMember
2232 Receivables due from other financial institutions Member wbk:ReceivablesDueFromOtherFinancialInstitutionsMember
2233 Loans Member wbk:LoansAndFinanceLeasesReceivableMember
2234 Regulatory deposits with central banks overseas Member wbk:MandatoryReserveDepositsAtCentralBanksMember
2235 Due from subsidiaries Member wbk:DueFromSubsidiariesMember
2236 Other financial assets Member wbk:OtherFinancialAssetsMember
2237 Classes of financial liabilities [axis] Axis ifrs-full:ClassesOfFinancialLiabilitiesAxis
2238 Financial liabilities, class [member] Member ifrs-full:FinancialLiabilitiesMember
2239 Payables due to other financial institutions Member wbk:PayablesDueToOtherFinancialInstitutionsMember
2240 Deposits and other borrowings Member wbk:DepositsAndOtherBorrowingsMember
2241 Debt issues Member wbk:DebtIssuesMember
2242 Due to subsidiaries Member wbk:DueToSubsidiariesMember
2243 Loan capital Member wbk:LoanCapitalMember
2244 Other financial liabilities Member wbk:OtherFinancialLiabilitiesMember
2245 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
2246 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
2247 Parent Entity Member us-gaap:ParentCompanyMember
2248 Fair values of financial assets and financial liabilities LineItems ifrs-full:DisclosureOfFinancialInstrumentsLineItems
2249 Financial assets, Carrying Amount Concept (Monetary) As Of Debit ifrs-full:FinancialAssets
2250 Financial liabilities, Carrying Amount Concept (Monetary) As Of Credit ifrs-full:FinancialLiabilities
2251 Financial assets, Fair Value Concept (Monetary) As Of Debit ifrs-full:FinancialAssetsAtFairValue
2252 Financial Liabilities, Fair Value Concept (Monetary) As Of Credit ifrs-full:FinancialLiabilitiesAtFairValue
2253 42401 - Disclosure - Offsetting financial assets and financial liabilities (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureOffsettingFinancialAssetsAndFinancialLiabilitiesDetails
2254 Disclosure Of Offsetting Of Financial Assets And Financial Liabilities [Table] Table

*

*

 wbk:DisclosureOfOffsettingOfFinancialAssetsAndFinancialLiabilitiesTable
2255 Classes of financial assets [axis] Axis ifrs-full:ClassesOfFinancialAssetsAxis
2256 Financial assets Member ifrs-full:FinancialAssetsMember
2257 Receivables due from other financial institutions Member wbk:ReceivablesDueFromOtherFinancialInstitutionsMember
2258 Derivative financial instruments Member wbk:DerivativeFinancialAssetsMember
2259 Securities purchased under agreement to resell Member wbk:SecuritiesPurchasedUnderAgreementToResellMember
2260 Loans Member wbk:LoansAndFinanceLeasesReceivableMember
2261 Other financial assets Member wbk:OtherFinancialAssetsMember
2262 Classes of financial liabilities [axis] Axis ifrs-full:ClassesOfFinancialLiabilitiesAxis
2263 Financial liabilities, class [member] Member ifrs-full:FinancialLiabilitiesMember
2264 Derivative financial instruments Member wbk:DerivativeFinancialLiabilitiesMember
2265 Security repurchase agreements Member wbk:SecurityRepurchaseAgreementsMember
2266 Deposits and other borrowings Member wbk:DepositsAndOtherBorrowingsMember
2267 Other financial liabilities Member wbk:OtherFinancialLiabilitiesMember
2268 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
2269 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
2270 Parent Entity Member us-gaap:ParentCompanyMember
2271 Offsetting financial assets and financial liabilities LineItems wbk:DisclosureOfOffsettingOfFinancialAssetsAndFinancialLiabilitiesLineItems
2272 Assets Abstract ifrs-full:NetFinancialAssetsSubjectToOffsettingEnforceableMasterNettingArrangementsOrSimilarAgreementsAbstract
2273 Effects of Offsetting on Balance Sheet Abstract ifrs-full:NetFinancialAssetsSubjectToOffsettingEnforceableMasterNettingArrangementsOrSimilarAgreementsInStatementOfFinancialPositionAbstract
2274 Gross Amounts Concept (Monetary) As Of Debit ifrs-full:GrossFinancialAssetsSubjectToOffsettingEnforceableMasterNettingArrangementsOrSimilarAgreements
2275 Amounts Offset Concept (Monetary) As Of Credit ifrs-full:GrossFinancialLiabilitiesSetOffAgainstFinancialAssetsSubjectToOffsettingEnforceableMasterNettingArrangementsOrSimilarAgreements
2276 Net Amounts Reported on the Balance Sheet Concept (Monetary) As Of Debit ifrs-full:NetFinancialAssetsSubjectToOffsettingEnforceableMasterNettingArrangementsOrSimilarAgreementsInStatementOfFinancialPosition
2277 Amounts Subject to Enforceable Netting Arrangements But Not Offset Abstract ifrs-full:AmountsSubjectToEnforceableMasterNettingArrangementOrSimilarAgreementNotSetOffAgainstFinancialAssetsAbstract
2278 Other Recognised Financial Instruments Concept (Monetary) As Of Credit ifrs-full:FinancialInstrumentsSubjectToEnforceableMasterNettingArrangementOrSimilarAgreementNotSetOffAgainstFinancialAssets
2279 Cash Collateral Concept (Monetary) As Of Credit ifrs-full:CashCollateralReceivedSubjectToEnforceableMasterNettingArrangementOrSimilarAgreementNotSetOffAgainstFinancialAssets
2280 Financial Instrument Collateral Concept (Monetary) As Of Credit wbk:FinancialInstrumentCollateralReceivedSubjectToEnforceableMasterNettingArrangementOrSimilarAgreementNotSetOffAgainstFinancialAssets
2281 Net Amount Concept (Monetary) As Of Debit ifrs-full:NetFinancialAssetsSubjectToOffsettingEnforceableMasterNettingArrangementsOrSimilarAgreements
2282 Liabilities Abstract ifrs-full:NetFinancialLiabilitiesSubjectToOffsettingEnforceableMasterNettingArrangementsOrSimilarAgreementsAbstract
2283 Effects of Offsetting on Balance Sheet Abstract ifrs-full:NetFinancialLiabilitiesSubjectToOffsettingEnforceableMasterNettingArrangementsOrSimilarAgreementsInStatementOfFinancialPositionAbstract
2284 Gross Amounts Concept (Monetary) As Of Credit ifrs-full:GrossFinancialLiabilitiesSubjectToOffsettingEnforceableMasterNettingArrangementsOrSimilarAgreements
2285 Amounts Offset Concept (Monetary) As Of Debit ifrs-full:GrossFinancialAssetsSetOffAgainstFinancialLiabilitiesSubjectToOffsettingEnforceableMasterNettingArrangementsOrSimilarAgreements
2286 Net Amounts Reported on the Balance Sheet Concept (Monetary) As Of Credit ifrs-full:NetFinancialLiabilitiesSubjectToOffsettingEnforceableMasterNettingArrangementsOrSimilarAgreementsInStatementOfFinancialPosition
2287 Amounts Subject to Enforceable Netting Arrangements But Not Offset Abstract ifrs-full:AmountsSubjectToEnforceableMasterNettingArrangementOrSimilarAgreementNotSetOffAgainstFinancialLiabilitiesAbstract
2288 Other Recognised Financial Instruments Concept (Monetary) As Of Debit ifrs-full:FinancialInstrumentsSubjectToEnforceableMasterNettingArrangementOrSimilarAgreementNotSetOffAgainstFinancialLiabilities
2289 Cash Collateral Concept (Monetary) As Of Debit ifrs-full:CashCollateralPledgedSubjectToEnforceableMasterNettingArrangementOrSimilarAgreementNotSetOffAgainstFinancialLiabilities
2290 Financial Instrument Collateral Concept (Monetary) As Of Debit wbk:FinancialInstrumentPledgedSubjectToEnforceableMasterNettingArrangementOrSimilarAgreementNotSetOffAgainstFinancialLiabilities
2291 Net Amount Concept (Monetary) As Of Credit ifrs-full:NetFinancialLiabilitiesSubjectToOffsettingEnforceableMasterNettingArrangementsOrSimilarAgreements
2292 42501 - Disclosure - Securitisation, covered bonds and other transferred assets (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureSecuritisationCoveredBondsAndOtherTransferredAssetsDetails
2293 Disclosure of transferred financial assets that are not derecognised in their entirety [table] Table

*

*

 ifrs-full:DisclosureOfFinancialAssetsTransferredDuringPeriodWhichDoNotQualifyForDerecognitionTable
2294 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
2295 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
2296 Parent Entity Member us-gaap:ParentCompanyMember
2297 Transferred financial assets that are not derecognised in their entirety [axis] Axis ifrs-full:FinancialAssetsWhichDoNotQualifyForDerecognitionAxis
2298 Transferred financial assets that are not derecognised in their entirety [member] Member ifrs-full:FinancialAssetsWhichDoNotQualifyForDerecognitionMember
2299 Securitisation - own assets Member wbk:SecuritisationOwnAssetsMember
2300 Customer conduits Member wbk:CustomerConduitsMember
2301 Covered bonds Member wbk:CoveredBondsMember
2302 Repurchase agreements Member wbk:IfrsRepurchaseAgreementsMember
2303 Securitisation, covered bonds and other transferred assets LineItems ifrs-full:DisclosureOfFinancialAssetsTransferredDuringPeriodWhichDoNotQualifyForDerecognitionLineItems
2304 Undrawn funding and liquidity facilities Concept (Monetary) As Of Credit wbk:UndrawnFundingAndLiquidityFacilities
2305 Number of covered bond programs Concept (Integer) As Of wbk:NumberOfCoveredBondPrograms
2306 Carrying amount of transferred assets Concept (Monetary) As Of Debit ifrs-full:AssetsThatEntityContinuesToRecognise
2307 Carrying amount of associated liabilities Concept (Monetary) As Of Credit ifrs-full:AssociatedLiabilitiesThatEntityContinuesToRecognise
2308 Fair value of transferred assets Concept (Monetary) As Of Debit ifrs-full:FairValueOfTransferredFinancialAssetsThatAreNotDerecognisedInTheirEntirety
2309 Fair value of associated liabilities Concept (Monetary) As Of Credit ifrs-full:FairValueOfAssociatedFinancialLiabilities
2310 Net fair value position Concept (Monetary) As Of Debit ifrs-full:FairValueOfTransferredFinancialAssetsAssociatedFinancialLiabilitiesThatAreNotDerecognisedInTheirEntirety
2311 42601 - Disclosure - Intangible assets - Useful life (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureIntangibleAssetsUsefulLifeDetails
2312 Disclosure of detailed information about intangible assets [table] Table

*

*

 ifrs-full:DisclosureOfIntangibleAssetsTable
2313 Range [axis] Axis ifrs-full:RangeAxis
2314 Ranges [member] Member ifrs-full:RangesMember
2315 Minimum Member ifrs-full:BottomOfRangeMember
2316 Maximum Member ifrs-full:TopOfRangeMember
2317 Classes of intangible assets other than goodwill [axis] Axis ifrs-full:ClassesOfIntangibleAssetsOtherThanGoodwillAxis
2318 Intangible assets other than goodwill [member] Member ifrs-full:IntangibleAssetsOtherThanGoodwillMember
2319 Computer software Member ifrs-full:ComputerSoftwareMember
2320 Core deposit intangibles Member wbk:CoreDepositIntangiblesMember
2321 Intangible assets LineItems ifrs-full:DisclosureOfIntangibleAssetsLineItems
2322 Useful life (in years) Concept (xbrli:durationItemType) For Period wbk:IfrsFiniteLivedIntangibleAssetUsefulLife
2323 42602 - Disclosure - Intangible assets - Changes in intangible assets and goodwill (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureIntangibleAssetsChangesInIntangibleAssetsAndGoodwillDetails
2324 Disclosure of reconciliation of changes in intangible assets and goodwill [table] Table

*

*

 ifrs-full:DisclosureOfReconciliationOfChangesInIntangibleAssetsAndGoodwillTable
2325 Classes of intangible assets and goodwill [axis] Axis ifrs-full:ClassesOfIntangibleAssetsAndGoodwillAxis
2326 Intangible assets and goodwill [member] Member ifrs-full:IntangibleAssetsAndGoodwillMember
2327 Computer software Member ifrs-full:ComputerSoftwareMember
2328 Brand Names Member ifrs-full:BrandNamesMember
2329 Core deposit intangibles Member wbk:CoreDepositIntangiblesMember
2330 Other intangibles Member ifrs-full:OtherIntangibleAssetsMember
2331 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
2332 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
2333 Parent Entity Member us-gaap:ParentCompanyMember
2334 Intangible assets LineItems ifrs-full:DisclosureOfReconciliationOfChangesInIntangibleAssetsAndGoodwillLineItems
2335 Goodwill Abstract ifrs-full:ReconciliationOfChangesInGoodwillAbstract
2336 Goodwill, opening balance Concept (Monetary) As Of Debit ifrs-full:Goodwill
2337 Disposals Concept (Monetary) For Period Credit ifrs-full:DecreaseThroughClassifiedAsHeldForSaleGoodwill
2338 Impairment Concept (Monetary) For Period ifrs-full:ImpairmentLossRecognisedInProfitOrLossGoodwill
2339 Other adjustments Concept (Monetary) For Period Debit ifrs-full:IncreaseDecreaseThroughTransfersAndOtherChangesGoodwill
2340 Goodwill, closing balance Concept (Monetary) As Of Debit ifrs-full:Goodwill
2341 Intangible assets other than goodwill Abstract ifrs-full:ReconciliationOfChangesInIntangibleAssetsOtherThanGoodwillAbstract
2342 Intangible assets, opening balance Concept (Monetary) As Of Debit ifrs-full:IntangibleAssetsOtherThanGoodwill
2343 Additions Concept (Monetary) For Period Debit ifrs-full:AdditionsOtherThanThroughBusinessCombinationsIntangibleAssetsOtherThanGoodwill
2344 Impairment Concept (Monetary) For Period ifrs-full:ImpairmentLossRecognisedInProfitOrLossIntangibleAssetsOtherThanGoodwill
2345 Amortisation Concept (Monetary) For Period ifrs-full:AmortisationIntangibleAssetsOtherThanGoodwill
2346 Other adjustments Concept (Monetary) For Period Debit ifrs-full:IncreaseDecreaseThroughTransfersAndOtherChangesIntangibleAssetsOtherThanGoodwill
2347 Intangible assets, closing balance Concept (Monetary) As Of Debit ifrs-full:IntangibleAssetsOtherThanGoodwill
2348 Total intangible assets Abstract wbk:TotalIntangibleAssetsAbstract
2349 Total intangible assets Concept (Monetary) As Of Debit ifrs-full:IntangibleAssetsAndGoodwill
2350 42603 - Disclosure - Intangible assets - Cost and accumulated amortisation and impairment (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureIntangibleAssetsCostAndAccumulatedAmortisationAndImpairmentDetails
2351 Disclosure of reconciliation of changes in intangible assets and goodwill [table] Table

*

*

 ifrs-full:DisclosureOfReconciliationOfChangesInIntangibleAssetsAndGoodwillTable
2352 Classes of intangible assets and goodwill [axis] Axis ifrs-full:ClassesOfIntangibleAssetsAndGoodwillAxis
2353 Intangible assets and goodwill [member] Member ifrs-full:IntangibleAssetsAndGoodwillMember
2354 Computer software Member ifrs-full:ComputerSoftwareMember
2355 Brand Names Member ifrs-full:BrandNamesMember
2356 Core deposit intangibles Member wbk:CoreDepositIntangiblesMember
2357 Other intangibles Member ifrs-full:OtherIntangibleAssetsMember
2358 Carrying amount, accumulated depreciation, amortisation and impairment and gross carrying amount [axis] Axis ifrs-full:CarryingAmountAccumulatedDepreciationAmortisationAndImpairmentAndGrossCarryingAmountAxis
2359 Carrying amount [member] Member ifrs-full:CarryingAmountMember
2360 Gross/Cost Member ifrs-full:GrossCarryingAmountMember
2361 Accumulated amortisation and impairment Member ifrs-full:AccumulatedDepreciationAmortisationAndImpairmentMember
2362 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
2363 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
2364 Parent Entity Member us-gaap:ParentCompanyMember
2365 Continuing and discontinued operations [axis] Axis ifrs-full:ContinuingAndDiscontinuedOperationsAxis
2366 Aggregate continuing and discontinued operations [member] Member ifrs-full:AggregateContinuingAndDiscontinuedOperationsMember
2367 Hastings' overseas operations and Hastings' Australian operations Member wbk:HastingsOverseasOperationsAndHastingsAustralianOperationsMember
2368 Intangible assets LineItems ifrs-full:DisclosureOfReconciliationOfChangesInIntangibleAssetsAndGoodwillLineItems
2369 Carrying amount Concept (Monetary) As Of Debit ifrs-full:IntangibleAssetsOtherThanGoodwill
2370 Goodwill derecognised due to sale Concept (Monetary) For Period Credit ifrs-full:DecreaseThroughClassifiedAsHeldForSaleGoodwill
2371 Impairment of goodwill Concept (Monetary) For Period ifrs-full:ImpairmentLossRecognisedInProfitOrLossGoodwill
2372 42604 - Disclosure - Intangible assets - Goodwill allocation (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureIntangibleAssetsGoodwillAllocationDetails
2373 Disclosure of reconciliation of changes in goodwill [table] Table

*

*

 ifrs-full:DisclosureOfReconciliationOfChangesInGoodwillTable
2374 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
2375 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
2376 Parent Entity Member us-gaap:ParentCompanyMember
2377 Geographical areas [axis] Axis ifrs-full:GeographicalAreasAxis
2378 Geographical areas [member] Member ifrs-full:GeographicalAreasMember
2379 Australia Member ifrs-full:CountryOfDomicileMember
2380 New Zealand Member country:NZ
2381 Individual assets or cash-generating units [axis] Axis ifrs-full:IndividualAssetsOrCashgeneratingUnitsAxis
2382 Entity's total for individual assets or cash-generating units [member] Member ifrs-full:EntitysTotalForIndividualAssetsOrCashgeneratingUnitsMember
2383 Consumer Bank Member wbk:ConsumerBankMember
2384 Business Bank Member wbk:BusinessBankMember
2385 Westpac Institutional Bank Member wbk:WestpacInstitutionalBankMember
2386 BT Financial Group (Australia) Member wbk:BtFinancialGroupAustraliaMember
2387 New Zealand Consumer Banking and Wealth Member wbk:NewZealandConsumerBankingAndWealthMember
2388 BT New Zealand Member wbk:BtNewZealandMember
2389 Hastings Member wbk:HastingsMember
2390 Goodwill allocation LineItems ifrs-full:DisclosureOfReconciliationOfChangesInGoodwillLineItems
2391 Total goodwill Concept (Monetary) As Of Debit ifrs-full:Goodwill
2392 Significant assumptions used in recoverable amount for goodwill Abstract wbk:SignificantAssumptionsUsedInRecoverableAmountForGoodwillAbstract
2393 Group's equity rate Concept (Percent) For Period wbk:WeightedAverageCostOfCapital
2394 Group's adjusted pre-tax equity rate Concept (Percent) For Period wbk:WeightedAveragePreTaxCostOfCapital
2395 42701 - Disclosure - Other assets (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureOtherAssetsDetails
2396 Disclosure of Other Assets [Table] Table

*

*

 wbk:DisclosureOfOtherAssetsTable
2397 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
2398 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
2399 Parent Entity Member us-gaap:ParentCompanyMember
2400 Other assets LineItems wbk:DisclosureOfOtherAssetsLineItems
2401 Accrued interest receivable Concept (Monetary) As Of Debit ifrs-full:InterestReceivable
2402 Securities sold not delivered Concept (Monetary) As Of Debit wbk:SecuritiesSoldNotDelivered
2403 Deferred acquisition costs Concept (Monetary) As Of Debit ifrs-full:DeferredAcquisitionCostsArisingFromInsuranceContracts
2404 Trade debtors Concept (Monetary) As Of Debit ifrs-full:TradeReceivables
2405 Prepayments Concept (Monetary) As Of Debit ifrs-full:Prepayments
2406 Accrued fees and commissions Concept (Monetary) As Of Debit ifrs-full:AccruedIncome
2407 Other Concept (Monetary) As Of Debit wbk:MiscellaneousOtherAssets
2408 Total other assets Concept (Monetary) As Of Debit ifrs-full:OtherAssets
2409 42801 - Disclosure - Provisions (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureProvisionsDetails
2410 Disclosure of other provisions [table] Table

*

*

 ifrs-full:DisclosureOfOtherProvisionsTable
2411 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
2412 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
2413 Parent Entity Member us-gaap:ParentCompanyMember
2414 Classes of other provisions [axis] Axis ifrs-full:ClassesOfProvisionsAxis
2415 Other provisions Member ifrs-full:OtherProvisionsMember
2416 Long Service Leave Member wbk:LongServiceLeaveMember
2417 Annual Leave and Other Employee Benefits Member wbk:AnnualLeaveAndOtherEmployeeBenefitsMember
2418 Litigation and Non-Lending Losses Member wbk:LitigationAndNonLendingLossesMember
2419 Provisions for Impairment on Credit Commitments Member ifrs-full:ProvisionForCreditCommitmentsMember
2420 Leasehold Premises Member wbk:LeaseholdPremisesMember
2421 Restructuring Provisions Member ifrs-full:RestructuringProvisionMember
2422 Compliance, Regulation and Remediation Provisions Member wbk:ComplianceRegulationAndRemediationProvisionsMember
2423 Geographical [Axis] Axis us-gaap:StatementGeographicalAxis
2424 Geographical [Domain] Member us-gaap:SegmentGeographicalDomain
2425 New South Wales Member wbk:NewSouthWalesMember
2426 Victoria Member wbk:VictoriaMember
2427 South Australia Member wbk:SouthAustraliaMember
2428 Queensland Member wbk:QueenslandMember
2429 Australian Capital Territory Member wbk:AustralianCapitalTerritoryMember
2430 Western Australia Member wbk:WesternAustraliaMember
2431 Tasmania Member wbk:TasmaniaMember
2432 Provisions LineItems ifrs-full:DisclosureOfOtherProvisionsLineItems
2433 Reconciliation of changes in other provisions Abstract ifrs-full:ReconciliationOfChangesInOtherProvisionsAbstract
2434 Balance at beginning of the year Concept (Monetary) As Of Credit ifrs-full:OtherProvisions
2435 Additions Concept (Monetary) For Period Credit ifrs-full:AdditionalProvisionsOtherProvisions
2436 Utilisation Concept (Monetary) For Period Debit ifrs-full:ProvisionUsedOtherProvisions
2437 Reversal of unutilised provisions Concept (Monetary) For Period Debit ifrs-full:UnusedProvisionReversedOtherProvisions
2438 Unwinding of discount Concept (Monetary) For Period Credit ifrs-full:IncreaseDecreaseThroughChangeInDiscountRateOtherProvisions
2439 Other Concept (Monetary) For Period Credit ifrs-full:IncreaseDecreaseThroughTransfersAndOtherChangesOtherProvisions
2440 Balance at end of the year Concept (Monetary) As Of Credit ifrs-full:OtherProvisions
2441 Legislative liabilities Abstract wbk:LegislativeLiabilitiesAbstract
2442 Actuarial assessment liability Concept (Monetary) As Of Credit wbk:ActuarialAssessmentLiability
2443 42901 - Disclosure - Other liabilities (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureOtherLiabilitiesDetails
2444 Disclosure of Other liabilities [Table] Table

*

*

 wbk:DisclosureOfOtherLiabilitiesTable
2445 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
2446 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
2447 Parent Entity Member us-gaap:ParentCompanyMember
2448 Other liabilities LineItems wbk:DisclosureOfOtherLiabilitiesLineItems
2449 Unearned insurance premiums Concept (Monetary) As Of Credit ifrs-full:UnearnedPremiums
2450 Outstanding insurance claims Concept (Monetary) As Of Credit ifrs-full:ClaimsReportedByPolicyholders
2451 Defined benefit deficit Concept (Monetary) As Of Credit ifrs-full:RecognisedLiabilitiesDefinedBenefitPlan
2452 Accrued interest payable Concept (Monetary) As Of Credit ifrs-full:InterestPayable
2453 Credit card loyalty program Concept (Monetary) As Of Credit wbk:CreditCardLoyaltyProgramPayable
2454 Securities purchased not delivered Concept (Monetary) As Of Credit wbk:SecuritiesPurchasedNotDelivered
2455 Trade creditors and other accrued expenses Concept (Monetary) As Of Credit ifrs-full:TradeAndOtherPayables
2456 Other Concept (Monetary) As Of Credit wbk:MiscellaneousOtherLiabilities
2457 Total other liabilities Concept (Monetary) As Of Credit ifrs-full:OtherLiabilities
2458 Provision for refunds and payments Concept (Monetary) As Of Credit ifrs-full:RefundsProvision
2459 43001 - Disclosure - Operating lease commitments (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureOperatingLeaseCommitmentsDetails
2460 Disclosure of finance lease and operating lease by lessee [table] Table

*

*

 ifrs-full:DisclosureOfFinanceLeaseAndOperatingLeaseByLesseeTable
2461 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
2462 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
2463 Parent Entity Member us-gaap:ParentCompanyMember
2464 Maturity [axis] Axis ifrs-full:MaturityAxis
2465 Aggregated time bands [member] Member ifrs-full:AggregatedTimeBandsMember
2466 No later than one year Member ifrs-full:NotLaterThanOneYearMember
2467 Over 1 Year to 5 Years Member ifrs-full:LaterThanOneYearAndNotLaterThanFiveYearsMember
2468 Over 5 Years Member ifrs-full:LaterThanFiveYearsMember
2469 Operating leases LineItems ifrs-full:DisclosureOfFinanceLeaseAndOperatingLeaseByLesseeLineItems
2470 Total lease commitments Concept (Monetary) As Of Credit ifrs-full:MinimumLeasePaymentsPayableUnderNoncancellableOperatingLease
2471 Future minimum lease payments receivable from non-cancellable sub-leases Concept (Monetary) As Of Debit ifrs-full:ExpectedFutureMinimumSubleasePaymentsReceivableUnderNoncancellableSubleasesClassifiedAsOperatingLease
2472 43101 - Disclosure - Contingent liabilities, contingent assets and credit commitments - Undrawn credit commitments excluding derivatives (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureContingentLiabilitiesContingentAssetsAndCreditCommitmentsUndrawnCreditCommitmentsExcludingDerivativesDetails
2473 Disclosure of contingent liabilities [table] Table

*

*

 ifrs-full:DisclosureOfContingentLiabilitiesTable
2474 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
2475 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
2476 Parent Entity Member us-gaap:ParentCompanyMember
2477 Maturity [axis] Axis ifrs-full:MaturityAxis
2478 Aggregated time bands [member] Member ifrs-full:AggregatedTimeBandsMember
2479 No later than one year Member ifrs-full:NotLaterThanOneYearMember
2480 Later than one year and not later than three years Member ifrs-full:LaterThanOneYearAndNotLaterThanThreeYearsMember
2481 Over 3 to 5 Years Member ifrs-full:LaterThanThreeYearsAndNotLaterThanFiveYearsMember
2482 Over 5 Years Member ifrs-full:LaterThanFiveYearsMember
2483 Contingent liabilities, contingent assets and credit commitments LineItems ifrs-full:DisclosureOfContingentLiabilitiesLineItems
2484 Letters of credit and guarantees Concept (Monetary) As Of Credit wbk:LettersOfCreditAndGuarantees
2485 Commitments to extend credit Concept (Monetary) As Of Credit wbk:CommitmentsToExtendCredit
2486 Other Concept (Monetary) As Of Credit wbk:OtherCommitments
2487 Total undrawn credit commitments Concept (Monetary) As Of Credit wbk:UndrawnCreditCommitments
2488 Commitments to customers, which had not yet been accepted Concept (Monetary) As Of Credit wbk:CommitmentsToCustomersButNotYetBeenAccepted
2489 43102 - Disclosure - Contingent liabilities, contingent assets and credit commitments - Contingent liabilities (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureContingentLiabilitiesContingentAssetsAndCreditCommitmentsContingentLiabilitiesDetails
2490 Disclosure of contingent liabilities [table] Table

*

*

 ifrs-full:DisclosureOfContingentLiabilitiesTable
2491 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
2492 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
2493 Parent Entity Member us-gaap:ParentCompanyMember
2494 Classes of contingent liabilities [axis] Axis ifrs-full:ClassesOfContingentLiabilitiesAxis
2495 Contingent liabilities [member] Member ifrs-full:ContingentLiabilitiesMember
2496 Legal proceedings Member ifrs-full:LegalProceedingsContingentLiabilityMember
2497 Guarantees Member ifrs-full:ContingentLiabilityForGuaranteesMember
2498 Contingent liabilities, contingent assets and credit commitments LineItems ifrs-full:DisclosureOfContingentLiabilitiesLineItems
2499 Number of customers for focus of claim Concept (Integer) As Of wbk:NumberOfSpecificCustomersForFocusOfClaim
2500 Number of planners operating in aligned dealer groups Concept (Integer) As Of wbk:NumberOfPlannersOperatingInAlignedDealerGroups
2501 Maximum deposits insured under FCS Concept (Monetary) As Of Debit wbk:CashDepositsFinancialClaimsSchemeInsuredAmountMaximum
2502 Maximum percentage of FCS levy Concept (Percent) As Of wbk:MaximumPercentageOfLevyOnContingentLiability
2503 Maximum contingent liability Concept (Monetary) As Of Credit wbk:MaximumContingentLiability
2504 43201 - Disclosure - Shareholders' equity - Share capital (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureShareholdersEquityShareCapitalDetails
2505 Disclosure of classes of share capital [table] Table

*

*

 ifrs-full:DisclosureOfClassesOfShareCapitalTable
2506 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
2507 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
2508 Parent Entity Member us-gaap:ParentCompanyMember
2509 Shareholders' equity LineItems ifrs-full:DisclosureOfClassesOfShareCapitalLineItems
2510 Ordinary share capital, fully paid Concept (Monetary) As Of Credit ifrs-full:IssuedCapital
2511 Treasury shares held for RSP Concept (Monetary) As Of Debit wbk:RestrictedSharePlanTreasuryShares
2512 Other treasury shares held Concept (Monetary) As Of Debit wbk:OtherTreasuryShares
2513 Total treasury shares held Concept (Monetary) As Of Debit ifrs-full:TreasuryShares
2514 Total share capital Concept (Monetary) As Of Credit wbk:IssuedCapitalNetOfTreasuryShares
2515 Non-controlling interests Concept (Monetary) As Of Credit ifrs-full:NoncontrollingInterests
2516 Number of shares in entity held by entity, unvested restricted shares Concept (Shares) As Of wbk:NumberOfSharesInEntityHeldByEntityUnvestedRestrictedShares
2517 Number of shares in entity held by entity or by its subsidiaries or associates, other Concept (Shares) As Of wbk:NumberOfSharesInEntityHeldByEntityOrByItsSubsidiariesOrAssociatesOther
2518 43202 - Disclosure - Shareholders' equity - Ordinary shares (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureShareholdersEquityOrdinarySharesDetails
2519 Disclosure of classes of share capital [table] Table

*

*

 ifrs-full:DisclosureOfClassesOfShareCapitalTable
2520 Classes of share capital [axis] Axis ifrs-full:ClassesOfShareCapitalAxis
2521 Share capital [member] Member ifrs-full:ClassesOfShareCapitalMember
2522 Ordinary shares Member ifrs-full:OrdinarySharesMember
2523 Shareholders' equity LineItems ifrs-full:DisclosureOfClassesOfShareCapitalLineItems
2524 Par value Concept (Share) As Of ifrs-full:ParValuePerShare
2525 Number of votes per ordinary shares Concept (Integer) For Period wbk:NumberOfVotesPerOrdinaryShares
2526 Reconciliation of movement in number of ordinary shares Abstract ifrs-full:ReconciliationOfNumberOfSharesOutstandingAbstract
2527 Number of shares outstanding at beginning of period Concept (Shares) As Of ifrs-full:NumberOfSharesOutstanding
2528 Dividend reinvestment plan Concept (Shares) For Period wbk:IncreaseThroughDividendReinvestmentPlan
2529 Conversion of Westpac Convertible Preference Shares Concept (Shares) For Period wbk:ConversionOfConvertiblePreferenceShares
2530 Number of shares outstanding at end of period Concept (Shares) As Of ifrs-full:NumberOfSharesOutstanding
2531 Dividend reinvestment plan - price per share for current year interim dividend Concept (Share) As Of wbk:PricePerShareInRelationToInterimDividendReinvestmentPlan
2532 Dividend reinvestment plan - price per share for prior year final dividend Concept (Share) As Of wbk:PricePerShareInRelationToFinalDividendReinvestmentPlan
2533 Conversion of Westpac Convertible Preference Shares - conversion Per Share Concept (Share) For Period wbk:ConversionOfConvertiblePreferenceSharesConversionPricePerShare
2534 43203 - Disclosure - Shareholders' equity - Ordinary shares purchased on market (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureShareholdersEquityOrdinarySharesPurchasedOnMarketDetails
2535 Disclosure of terms and conditions of share-based payment arrangement [table] Table

*

*

 ifrs-full:DisclosureOfTermsAndConditionsOfSharebasedPaymentArrangementTable
2536 Types of share-based payment arrangements [axis] Axis ifrs-full:TypesOfSharebasedPaymentArrangementsAxis
2537 Share-based payment arrangements [member] Member ifrs-full:SharebasedPaymentArrangementsMember
2538 Employee Share Plan (ESP) Member wbk:EmployeeSharePlanMember
2539 Restricted Share Plan (RSP) Member wbk:RestrictedSharePlanMember
2540 Westpac Performance Plan (WPP) Member wbk:WestpacPerformancePlanMember
2541 Westpac Long Term Incentive Plan (LTIP) Member wbk:WestpacLongTermIncentivePlanMember
2542 IFRS Award Type [Axis] Axis wbk:IfrsAwardTypeAxis
2543 IFRS Equity Award [Domain] Member wbk:IfrsEquityAwardDomain
2544 Share rights Member wbk:ShareRightsMember
2545 Share options Member wbk:IfrsEmployeeStockOptionMember
2546 Share-based payments LineItems ifrs-full:DisclosureOfTermsAndConditionsOfSharebasedPaymentArrangementLineItems
2547 Number of ordinary shares purchased on market Concept (Shares) For Period wbk:NumberOfOrdinarySharesPurchasedOnMarketShareBasedPaymentArrangements
2548 Number of treasury shares purchased, excluding RSP Concept (Shares) For Period wbk:NumberOfTreasurySharesPurchased
2549 Number of treasury shares sold Concept (Shares) For Period wbk:NumberOfTreasurySharesSold
2550 Net number of ordinary shares purchased/(sold) on market Concept (Shares) For Period wbk:NumberOfOrdinarySharesPurchasedSoldOnMarket
2551 Average share price, ordinary shares Concept (Monetary) For Period ifrs-full:WeightedAverageSharePrice
2552 Treasury shares purchased - average price Concept (Monetary) For Period wbk:TreasurySharesPurchasedAveragePrice
2553 Treasury shares sold - average price Concept (Monetary) For Period wbk:TreasurySharesSoldAveragePrice
2554 Average exercise price, options Concept (Monetary) For Period ifrs-full:WeightedAverageExercisePriceOfShareOptionsExercisedInSharebasedPaymentArrangement
2555 Tax benefit on purchase of ordinary shares on market Concept (Monetary) For Period Credit wbk:TaxBenefitOnPurchaseOfOrdinarySharesOnMarket
2556 43204 - Disclosure - Shareholders' equity - Reconciliation of movement in reserves (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureShareholdersEquityReconciliationOfMovementInReservesDetails
2557 Disclosure of reserves within equity [table] Table

*

*

 ifrs-full:DisclosureOfReservesWithinEquityTable
2558 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
2559 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
2560 Parent Entity Member us-gaap:ParentCompanyMember
2561 Shareholders' equity LineItems ifrs-full:DisclosureOfReservesWithinEquityLineItems
2562 Available-for-sale securities reserve Abstract ifrs-full:AvailableforsaleFinancialAssetsAbstract
2563 Opening balance Concept (Monetary) As Of Credit ifrs-full:ReserveOfGainsAndLossesOnRemeasuringAvailableforsaleFinancialAssets
2564 Net gains/(losses) from changes in fair value Concept (Monetary) For Period Credit wbk:GainsLossesOnRemeasuringAvailableForSaleFinancialAssetsBeforeTaxExcludingExchangeDifferences
2565 Income tax effect Concept (Monetary) For Period Debit wbk:GainsLossesOnRemeasuringAvailableForSaleFinancialAssetsTax
2566 Transferred to income statements Concept (Monetary) For Period Debit ifrs-full:ReclassificationAdjustmentsOnAvailableforsaleFinancialAssetsBeforeTax
2567 Income tax effect Concept (Monetary) For Period Credit wbk:ReclassificationAdjustmentsOnAvailableForSaleFinancialAssetsTax
2568 Exchange differences Concept (Monetary) For Period Credit wbk:ExchangeDifferencesRelatingToAvailableForSaleFinancialAssets
2569 Closing balance Concept (Monetary) As Of Credit ifrs-full:ReserveOfGainsAndLossesOnRemeasuringAvailableforsaleFinancialAssets
2570 Share-based payment reserve Abstract wbk:ShareBasedPaymentsReserveAbstract
2571 Opening balance Concept (Monetary) As Of Credit ifrs-full:ReserveOfSharebasedPayments
2572 Share-based payment expense Concept (Monetary) For Period Credit ifrs-full:IncreaseDecreaseThroughSharebasedPaymentTransactions
2573 Closing balance Concept (Monetary) As Of Credit ifrs-full:ReserveOfSharebasedPayments
2574 Cash flow hedge reserve Abstract ifrs-full:CashFlowHedgesAbstract
2575 Opening balance Concept (Monetary) As Of Credit ifrs-full:ReserveOfCashFlowHedges
2576 Net gains/(losses) from changes in fair value Concept (Monetary) For Period Credit ifrs-full:GainsLossesOnCashFlowHedgesBeforeTax
2577 Income tax effect Concept (Monetary) For Period Debit wbk:GainsLossesOnCashFlowHedgesTax
2578 Transferred to income statements Concept (Monetary) For Period Debit ifrs-full:ReclassificationAdjustmentsOnCashFlowHedgesBeforeTax
2579 Income tax effect Concept (Monetary) For Period Credit wbk:ReclassificationAdjustmentsOnCashFlowHedgesTax
2580 Closing balance Concept (Monetary) As Of Credit ifrs-full:ReserveOfCashFlowHedges
2581 Foreign currency translation reserve Abstract ifrs-full:ExchangeDifferencesOnTranslationAbstract
2582 Opening balance Concept (Monetary) As Of Credit ifrs-full:ReserveOfExchangeDifferencesOnTranslation
2583 Exchange differences on translation of foreign operations (net of associated hedges) Concept (Monetary) For Period Credit ifrs-full:GainsLossesOnExchangeDifferencesOnTranslationNetOfTax
2584 Transferred to income statements Concept (Monetary) For Period Debit ifrs-full:ReclassificationAdjustmentsOnExchangeDifferencesOnTranslationNetOfTax
2585 Closing balance Concept (Monetary) As Of Credit ifrs-full:ReserveOfExchangeDifferencesOnTranslation
2586 Other reserves Abstract wbk:MiscellaneousOtherReservesAbstract
2587 Opening balance Concept (Monetary) As Of Credit wbk:ReserveForMiscellaneousOtherReserves
2588 Transactions with owners Concept (Monetary) For Period Credit ifrs-full:IncreaseDecreaseThroughTransactionsWithOwners
2589 Closing balance Concept (Monetary) As Of Credit wbk:ReserveForMiscellaneousOtherReserves
2590 Total other reserves Concept (Monetary) As Of Credit ifrs-full:OtherReserves
2591 43301 - Disclosure - Capital adequacy (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureCapitalAdequacyDetails
2592 Implied Table Table

*

*

 implied:Table
2593 Capital adequacy Abstract wbk:DisclosureOfRegulatoryCapitalRequirementsUnderBankingRegulationsAbstract
2594 Minimum requirement of Common Equity Tier 1 (CET1) Concept (Pure) As Of wbk:CommonEquityTierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssets
2595 Minimum requirement of Tier 1 capital ratio Concept (Pure) As Of wbk:TierOneRiskBasedCapitalForMinimumReservesToRiskWeightedAssets
2596 Minimum requirement of Total Regulatory Capital ratio Concept (Pure) As Of wbk:CapitalRequiredForMinimumReservesToRiskWeightedAssets
2597 Capital conservation buffer Concept (Pure) As Of wbk:CapitalConservationBuffer
2598 Capital conservation buffer, surcharge Concept (Pure) As Of wbk:CapitalConservationBufferSurcharge
2599 Countercyclical capital buffer Concept (Pure) As Of wbk:CountercyclicalCapitalBuffer
2600 Common Equity Tier 1, interim preferred ratio Concept (Pure) As Of wbk:CommonEquityTierOneInterimPreferredRatio
2601 43401 - Disclosure - Dividends (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureDividendsDetails
2602 Disclosure of Dividends [Table] Table

*

*

 wbk:DisclosureOfDividendsTable
2603 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
2604 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
2605 Parent Entity Member us-gaap:ParentCompanyMember
2606 Geographical areas [axis] Axis ifrs-full:GeographicalAreasAxis
2607 Geographical areas [member] Member ifrs-full:GeographicalAreasMember
2608 Australia Member ifrs-full:CountryOfDomicileMember
2609 New Zealand Member country:NZ
2610 Dividends LineItems wbk:DisclosureOfDividendsLineItems
2611 Dividends not recognised at year end and proposed final dividend 94 cents per share (2017: 94 cents, 2016: 94 cents) all fully franked at 30% Concept (Monetary) For Period ifrs-full:DividendsProposedOrDeclaredBeforeFinancialStatementsAuthorisedForIssueButNotRecognisedAsDistributionToOwners
2612 Proposed final dividend per share Concept (Share) For Period ifrs-full:DividendsProposedOrDeclaredBeforeFinancialStatementsAuthorisedForIssueButNotRecognisedAsDistributionToOwnersPerShare
2613 Dividend tax rate (as a percent) Concept (Percent) For Period wbk:RateOfDividendDistributionTax
2614 Franking credits Concept (Monetary) For Period Credit wbk:FrankingCreditsAvailableAmount
2615 Imputation credits per share Concept (Share) For Period wbk:ImputationCreditsPerShare
2616 Imputation credits Concept (Monetary) For Period Credit wbk:ImputationCreditsAvailableAmount
2617 43501 - Disclosure - Investments in subsidiaries and associates - Material controlled entities and material controlled entities not wholly owned (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureInvestmentsInSubsidiariesAndAssociatesMaterialControlledEntitiesAndMaterialControlledEntitiesNotWhollyOwnedDetails
2618 Disclosure of subsidiaries [table] Table

*

*

 ifrs-full:DisclosureOfSignificantInvestmentsInSubsidiariesTable
2619 Subsidiaries [axis] Axis ifrs-full:SignificantInvestmentsInSubsidiariesAxis
2620 Entity's total for subsidiaries [member] Member ifrs-full:EntitysTotalForSubsidiariesMember
2621 St.George Motor Finance Limited Member wbk:St.georgeMotorFinanceLimitedMember
2622 Westpac Bank-PNG-Limited Member wbk:WestpacBankPngLimitedMember
2623 Westpac NZ Covered Bond Limited Member wbk:WestpacNzCoveredBondLimitedMember
2624 Westpac NZ Securitisation Limited Member wbk:WestpacNzSecuritisationLimitedMember
2625 Material controlled entities LineItems ifrs-full:DisclosureOfSignificantInvestmentsInSubsidiariesLineItems
2626 Percentage of equity owned by parent Concept (Percent) For Period ifrs-full:ProportionOfOwnershipInterestInSubsidiary
2627 43502 - Disclosure - Investments in subsidiaries and associates - Associates (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureInvestmentsInSubsidiariesAndAssociatesAssociatesDetails
2628 Disclosure of associates [table] Table

*

*

 ifrs-full:DisclosureOfSignificantInvestmentsInAssociatesTable
2629 Associates [axis] Axis ifrs-full:SignificantInvestmentsInAssociatesAxis
2630 Entity's total for associates [member] Member ifrs-full:EntitysTotalForAssociatesMember
2631 Pendal Group Limited Member wbk:PendalGroupLimitedMember
2632 Investments in subsidiaries and associates LineItems ifrs-full:DisclosureOfSignificantInvestmentsInAssociatesLineItems
2633 Number of associates material to the Group Concept (Integer) As Of wbk:NumberOfAssociates
2634 Number of shares sold under investment in associates Concept (Shares) For Period wbk:InvestmentInAssociatesSharesSold
2635 Holding percentage of available-for-sale securities Concept (Percent) For Period wbk:HoldingPercentageOfAvailableForSaleSecurities
2636 Ownership in associate (as a percent) Concept (Percent) For Period ifrs-full:ProportionOfOwnershipInterestInAssociate
2637 43503 - Disclosure - Investments in subsidiaries and associates - Associates, Summarised results (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureInvestmentsInSubsidiariesAndAssociatesAssociatesSummarisedResultsDetails
2638 Disclosure of associates [table] Table

*

*

 ifrs-full:DisclosureOfSignificantInvestmentsInAssociatesTable
2639 Associates [axis] Axis ifrs-full:SignificantInvestmentsInAssociatesAxis
2640 Entity's total for associates [member] Member ifrs-full:EntitysTotalForAssociatesMember
2641 Pendal Group Limited Member wbk:PendalGroupLimitedMember
2642 Investments in subsidiaries and associates LineItems ifrs-full:DisclosureOfSignificantInvestmentsInAssociatesLineItems
2643 Summarised results Abstract wbk:SummaryOfFinancialInformationOfAssociatesAbstract
2644 Revenue for the period Concept (Monetary) For Period Credit ifrs-full:Revenue
2645 Net profit for the period Concept (Monetary) For Period Credit ifrs-full:ProfitLoss
2646 Net other comprehensive income for the year Concept (Monetary) For Period Credit ifrs-full:OtherComprehensiveIncome
2647 Total comprehensive income Concept (Monetary) For Period Credit ifrs-full:ComprehensiveIncome
2648 Group's share of net profit Concept (Monetary) For Period Credit wbk:ShareOfProfitLossFromContinuingOperationsOfAssociatesAndJointVenturesAccountedForUsingEquityMethodBeforeEquityAdjustments
2649 Equity accounting adjustments Concept (Monetary) For Period Debit wbk:ShareOfProfitLossFromContinuingOperationsOfAssociatesAndJointVenturesAccountedForUsingEquityMethodEquityAccountingAdjustments
2650 Group's share in net profit recognised in the income statement Concept (Monetary) For Period Credit ifrs-full:ShareOfProfitLossOfContinuingOperationsOfAssociatesAndJointVenturesAccountedForUsingEquityMethod
2651 Group's share of other comprehensive income Concept (Monetary) For Period Credit ifrs-full:ShareOfOtherComprehensiveIncomeOfAssociatesAndJointVenturesAccountedForUsingEquityMethod
2652 Tax effect on Group's share of other comprehensive income Concept (Monetary) For Period Debit ifrs-full:IncomeTaxRelatingToShareOfOtherComprehensiveIncomeOfAssociatesAndJointVenturesAccountedForUsingEquityMethod
2653 Share of total comprehensive income recognised by the Group Concept (Monetary) For Period Credit ifrs-full:ShareOfTotalComprehensiveIncomeOfAssociatesAndJointVenturesAccountedForUsingEquityMethod
2654 Dividends received from associates during the period Concept (Monetary) For Period Debit ifrs-full:DividendsReceived
2655 43504 - Disclosure - Investments in subsidiaries and associates - Associates, Summarised balance sheet (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureInvestmentsInSubsidiariesAndAssociatesAssociatesSummarisedBalanceSheetDetails
2656 Disclosure of associates [table] Table

*

*

 ifrs-full:DisclosureOfSignificantInvestmentsInAssociatesTable
2657 Associates [axis] Axis ifrs-full:SignificantInvestmentsInAssociatesAxis
2658 Entity's total for associates [member] Member ifrs-full:EntitysTotalForAssociatesMember
2659 Pendal Group Limited Member wbk:PendalGroupLimitedMember
2660 Investments in subsidiaries and associates LineItems ifrs-full:DisclosureOfSignificantInvestmentsInAssociatesLineItems
2661 Summarised balance sheet Abstract wbk:SummaryOfBalanceSheetForAssociatesAbstract
2662 Total assets Concept (Monetary) As Of Debit ifrs-full:Assets
2663 Liabilities Concept (Monetary) As Of Credit ifrs-full:Liabilities
2664 Net assets/(net liabilities) Concept (Monetary) As Of Debit ifrs-full:NetAssetsLiabilities
2665 Group's share of total net assets Concept (Monetary) As Of Debit wbk:ShareOfTotalNetAssetsOfAssociatesAndJointVenturesAccountedForUsingEquityMethod
2666 Fair value adjustments (including notional goodwill) on acquisition (net of amortisation) Concept (Monetary) As Of Debit wbk:FairValueAdjustmentsOnAcquisition
2667 Carrying amount of interest in Pendal Group Limited Concept (Monetary) As Of Debit ifrs-full:InvestmentsInAssociates
2668 Carrying amount of interest in Pendal Group Limited sold Concept (Monetary) As Of Credit wbk:InvestmentsInAssociatesSold
2669 Carrying amount of remaining interest reclassified to available-for-sale securities Concept (Monetary) As Of Credit wbk:CarryingAmountOfRemainingInterestReclassifiedToAvailableForSaleSecurities
2670 Fair value of remaining interest reclassified to available-for-sale securities Concept (Monetary) As Of Debit wbk:FairValueOfRemainingInterestReclassifiedToAvailableForSaleSecurities
2671 Proceeds from sale of Pendal Group Limited interest, net of transaction costs Concept (Monetary) For Period Debit ifrs-full:ProceedsFromSalesOfInterestsInAssociates
2672 Amount of reserves recycled to profit or loss Concept (Monetary) As Of Credit wbk:AmountOfReservesRecycledToProfitOrLoss
2673 Gain on sale of interest in Pendal Group Limited Concept (Monetary) For Period Credit ifrs-full:GainsOnDisposalsOfInvestments
2674 43505 - Disclosure - Investments in subsidiaries and associates - Changes in ownership of subsidiaries (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureInvestmentsInSubsidiariesAndAssociatesChangesInOwnershipOfSubsidiariesDetails
2675 Disclosure of subsidiaries [table] Table

*

*

 ifrs-full:DisclosureOfSignificantInvestmentsInSubsidiariesTable
2676 Subsidiaries [axis] Axis ifrs-full:SignificantInvestmentsInSubsidiariesAxis
2677 Entity's total for subsidiaries [member] Member ifrs-full:EntitysTotalForSubsidiariesMember
2678 Hastings offshore subsidiaries Member wbk:HastingsOffshoreSubsidiariesSoldToNorthillCapitalMember
2679 Banking operations in Solomon Islands and Vanuatu Member wbk:BankingOperationsInSolomonIslandsAndVanuatuMember
2680 Changes in ownership of subsidiaries LineItems ifrs-full:DisclosureOfSignificantInvestmentsInSubsidiariesLineItems
2681 Gain (loss) on businesses disposed during the year Concept (Monetary) For Period Credit ifrs-full:GainsLossesRecognisedWhenControlInSubsidiaryIsLost
2682 Cash consideration received (paid), net of transaction costs and cash held Concept (Monetary) For Period Debit ifrs-full:CashFlowsFromLosingControlOfSubsidiariesOrOtherBusinessesClassifiedAsInvestingActivities
2683 43601 - Disclosure - Structured entities (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureStructuredEntitiesDetails
2684 Disclosure of information about consolidated structured entities [table] Table

*

*

 ifrs-full:DisclosureOfInformationAboutConsolidatedStructuredEntitiesTable
2685 Consolidated structured entities [axis] Axis ifrs-full:ConsolidatedStructuredEntitiesAxis
2686 Entity's total for consolidated structured entities [member] Member ifrs-full:EntitysTotalForConsolidatedStructuredEntitiesMember
2687 Investment in Third Party Mortgage and Other Asset-Backed Securities Member ifrs-full:AssetbackedFinancingsMember
2688 Financing to Securitisation Vehicles Member ifrs-full:SecuritisationVehiclesMember
2689 Group Managed Funds Member ifrs-full:InvestmentFundsMember
2690 Interest in Other Structured Entities Member wbk:InterestInOtherStructuredEntitiesMember
2691 Classes of assets [axis] Axis ifrs-full:ClassesOfAssetsAxis
2692 Assets [member] Member ifrs-full:ClassesOfAssetsMember
2693 Receivables due from other financial institutions Member wbk:ReceivablesDueFromOtherFinancialInstitutionsMember
2694 Trading securities and financial assets designated at fair value Member wbk:TradingSecuritiesAndFinancialAssetsDesignatedAtFairValueMember
2695 Available-for-sale securities Member wbk:IfrsAvailableForSaleSecuritiesMember
2696 Loans Member wbk:IfrsLoansReceivableMember
2697 Life insurance assets Member wbk:LifeInsuranceAssetsMember
2698 Other assets Member ifrs-full:OtherAssetsMember
2699 Structured entities LineItems ifrs-full:DisclosureOfInformationAboutConsolidatedStructuredEntitiesLineItems
2700 Total on-balance sheet exposures Concept (Monetary) As Of Debit wbk:BalanceSheetExposureToLossFromInterestsInStructuredEntities
2701 Total notional amounts of off-balance sheet exposures Concept (Monetary) As Of wbk:NotionalAmountsOfOffBalanceSheetExposureToLossFromInterestsInStructuredEntities
2702 Maximum exposure to loss Concept (Monetary) As Of ifrs-full:MaximumExposureToLossFromInterestsInStructuredEntities
2703 Size of structured entities Concept (Monetary) As Of Debit wbk:SizeOfStructuredEntities
2704 43701 - Disclosure - Share-based payments - Summary of plans (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureShareBasedPaymentsSummaryOfPlansDetails
2705 Disclosure of terms and conditions of share-based payment arrangement [table] Table

*

*

 ifrs-full:DisclosureOfTermsAndConditionsOfSharebasedPaymentArrangementTable
2706 Types of share-based payment arrangements [axis] Axis ifrs-full:TypesOfSharebasedPaymentArrangementsAxis
2707 Share-based payment arrangements [member] Member ifrs-full:SharebasedPaymentArrangementsMember
2708 Westpac Long Term Incentive Plan (LTIP) Member wbk:WestpacLongTermIncentivePlanMember
2709 Westpac Performance Plan (WPP) Member wbk:WestpacPerformancePlanMember
2710 Restricted Share Plan (RSP) Member wbk:RestrictedSharePlanMember
2711 Employee Share Plan (ESP) Member wbk:EmployeeSharePlanMember
2712 IFRS Award Type [Axis] Axis wbk:IfrsAwardTypeAxis
2713 IFRS Equity Award [Domain] Member wbk:IfrsEquityAwardDomain
2714 Restricted shares Member wbk:IfrsRestrictedStockMember
2715 Share rights Member wbk:ShareRightsMember
2716 IFRS Award Date [Axis] Axis wbk:IfrsAwardDateAxis
2717 IFRS Award Date [Domain] Member wbk:IfrsAwardDateDomain
2718 Awards prior to 2011 Member wbk:PriorTo2011Member
2719 2011 to 2014 Award Dates Member wbk:AwardDates2011To2014Member
2720 2015 Awards Member wbk:AwardDatesIn2015Member
2721 Share-based payments LineItems ifrs-full:DisclosureOfTermsAndConditionsOfSharebasedPaymentArrangementLineItems
2722 Cost of shares allocated Concept (Monetary) For Period Debit wbk:SharebasedPaymentArrangementCostOfSharesAllocated
2723 Threshold amount of shares allocated at free of cost per employee Concept (Monetary) For Period Debit wbk:ThresholdPriceOfSharesAllocatedToEmployees
2724 Exercise price Concept (Monetary) As Of ifrs-full:WeightedAverageExercisePriceOfOtherEquityInstrumentsOutstandingInSharebasedPaymentArrangement
2725 Performance period Concept (xbrli:durationItemType) For Period wbk:SharebasedPaymentArrangementPerformancePeriod
2726 Performance period, cash EPS (CAGR) Concept (xbrli:durationItemType) For Period wbk:SharebasedPaymentArrangementCashEpsCompoundAnnualGrowthRatePerformancePeriod
2727 Holding lock period Concept (xbrli:durationItemType) For Period wbk:SharebasedPaymentArrangementHoldingLockPeriod
2728 Service conditions Concept (xbrli:durationItemType) For Period wbk:SharebasedPaymentArrangementServiceConditionShareRetentionPeriod
2729 Vesting period Concept (xbrli:durationItemType) For Period wbk:SharebasedPaymentArrangementVestingPeriod
2730 Term of award Concept (xbrli:durationItemType) For Period wbk:SharebasedPaymentArrangementTermOfAward
2731 43702 - Disclosure - Share-based payments - Westpac Long Term Incentive Plan, Westpac Performance Plan (WPP) & Restricted Share Plan (RSP) (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureShareBasedPaymentsWestpacLongTermIncentivePlanWestpacPerformancePlanWppRestrictedSharePlanRspDetails
2732 Disclosure of terms and conditions of share-based payment arrangement [table] Table

*

*

 ifrs-full:DisclosureOfTermsAndConditionsOfSharebasedPaymentArrangementTable
2733 Types of share-based payment arrangements [axis] Axis ifrs-full:TypesOfSharebasedPaymentArrangementsAxis
2734 Share-based payment arrangements [member] Member ifrs-full:SharebasedPaymentArrangementsMember
2735 Westpac Long Term Incentive Plan (LTIP) Member wbk:WestpacLongTermIncentivePlanMember
2736 Westpac Performance Plan (WPP) Member wbk:WestpacPerformancePlanMember
2737 Restricted Share Plan (RSP) Member wbk:RestrictedSharePlanMember
2738 IFRS Award Type [Axis] Axis wbk:IfrsAwardTypeAxis
2739 IFRS Equity Award [Domain] Member wbk:IfrsEquityAwardDomain
2740 Share options Member wbk:IfrsEmployeeStockOptionMember
2741 Share rights Member wbk:ShareRightsMember
2742 IFRS Vesting [Axis] Axis wbk:IfrsVestingAxis
2743 IFRS Vesting [Domain] Member wbk:IfrsVestingDomain
2744 One-year vesting period Member wbk:OneYearVestingPeriodMember
2745 Two-year vesting period Member wbk:TwoYearVestingPeriodMember
2746 Three-year vesting period Member wbk:ThreeYearVestingPeriodMember
2747 Four-year vesting period Member wbk:FourYearVestingPeriodMember
2748 IFRS Award Date [Axis] Axis wbk:IfrsAwardDateAxis
2749 IFRS Award Date [Domain] Member wbk:IfrsAwardDateDomain
2750 Granted prior to October 2009 Member wbk:GrantedPriorToOctober2009Member
2751 Granted subsequent to October 2009 Member wbk:GrantedSubsequentToOctober2009Member
2752 Share-based payments LineItems ifrs-full:DisclosureOfTermsAndConditionsOfSharebasedPaymentArrangementLineItems
2753 Share options Abstract wbk:ShareOptionsAbstract
2754 Outstanding at the beginning of the year Concept (Decimal) As Of ifrs-full:NumberOfOutstandingShareOptions
2755 Options exercised during the year Concept (Decimal) For Period ifrs-full:NumberOfShareOptionsExercisedInSharebasedPaymentArrangement
2756 Lapsed during the year Concept (Decimal) For Period ifrs-full:NumberOfShareOptionsExpiredInSharebasedPaymentArrangement
2757 Outstanding at the end of the year Concept (Decimal) As Of ifrs-full:NumberOfOutstandingShareOptions
2758 Outstanding and Exercisable at the end of the year Concept (Decimal) As Of ifrs-full:NumberOfShareOptionsExercisableInSharebasedPaymentArrangement
2759 Weighted Average Exercise Price Abstract wbk:WeightedAverageExercisePriceAbstract
2760 Outstanding at the beginning of the year Concept (Monetary) As Of ifrs-full:WeightedAverageExercisePriceOfShareOptionsOutstandingInSharebasedPaymentArrangement
2761 Exercised during the year Concept (Monetary) For Period ifrs-full:WeightedAverageExercisePriceOfShareOptionsExercisedInSharebasedPaymentArrangement
2762 Outstanding at the end of the year Concept (Monetary) As Of ifrs-full:WeightedAverageExercisePriceOfShareOptionsOutstandingInSharebasedPaymentArrangement
2763 Outstanding and Exercisable at the end of the year Concept (Monetary) As Of ifrs-full:WeightedAverageExercisePriceOfShareOptionsExercisableInSharebasedPaymentArrangement
2764 Weighted average remaining contractual life Concept (Decimal) As Of ifrs-full:WeightedAverageRemainingContractualLifeOfOutstandingShareOptions
2765 Equity instruments other than options Abstract wbk:EquityInstrumentsOtherThanOptionsAbstract
2766 Outstanding at the beginning of the year Concept (Decimal) As Of ifrs-full:NumberOfOtherEquityInstrumentsOutstandingInSharebasedPaymentArrangement
2767 Granted during the year Concept (Decimal) For Period ifrs-full:NumberOfInstrumentsOtherEquityInstrumentsGranted
2768 Released Concept (Decimal) For Period wbk:NumberOfOtherEquityInstrumentsReleasedInShareBasedPaymentArrangement
2769 Forfeited during the year Concept (Decimal) For Period ifrs-full:NumberOfOtherEquityInstrumentsForfeitedInSharebasedPaymentArrangement
2770 Equity instruments exercised during the year Concept (Decimal) For Period ifrs-full:NumberOfOtherEquityInstrumentsExercisedOrVestedInSharebasedPaymentArrangement
2771 Lapsed during the year Concept (Decimal) For Period ifrs-full:NumberOfOtherEquityInstrumentsExpiredInSharebasedPaymentArrangement
2772 Outstanding at the end of the year Concept (Decimal) As Of ifrs-full:NumberOfOtherEquityInstrumentsOutstandingInSharebasedPaymentArrangement
2773 Outstanding and Exercisable at the end of the year Concept (Decimal) As Of ifrs-full:NumberOfOtherEquityInstrumentsExercisableInSharebasedPaymentArrangement
2774 Weighted average remaining contractual life Concept (xbrli:durationItemType) For Period wbk:WeightedAverageRemainingContractualLifeOfOtherEquityInstruments
2775 Weighted average fair value at grant date Concept (Monetary) As Of Credit ifrs-full:WeightedAverageFairValueAtMeasurementDateOtherEquityInstrumentsGranted
2776 43703 - Disclosure - Share-based payments - Employee Share Plan (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureShareBasedPaymentsEmployeeSharePlanDetails
2777 Disclosure of terms and conditions of share-based payment arrangement [table] Table

*

*

 ifrs-full:DisclosureOfTermsAndConditionsOfSharebasedPaymentArrangementTable
2778 Types of share-based payment arrangements [axis] Axis ifrs-full:TypesOfSharebasedPaymentArrangementsAxis
2779 Share-based payment arrangements [member] Member ifrs-full:SharebasedPaymentArrangementsMember
2780 Employee Share Plan (ESP) Member wbk:EmployeeSharePlanMember
2781 Share-based payments LineItems ifrs-full:DisclosureOfTermsAndConditionsOfSharebasedPaymentArrangementLineItems
2782 Number of Participants Concept (Integer) For Period wbk:SharebasedPaymentArrangementNumberOfParticipants
2783 Average Number of Shares Allocated per Participant Concept (Shares) For Period wbk:SharebasedPaymentArrangementAverageNumberOfSharesAllocatedPerParticipant
2784 Total Number of Shares Allocated Concept (Decimal) For Period ifrs-full:NumberOfInstrumentsOtherEquityInstrumentsGranted
2785 Market Price per Share Concept (Share) For Period wbk:SharebasedPaymentArrangementMarketPricePerShare
2786 Total Fair Value Concept (Monetary) For Period Debit wbk:SharebasedPaymentArrangementTotalFairValueOfSharesGranted
2787 Other employee benefits Concept (Monetary) For Period Debit ifrs-full:OtherLongtermBenefits
2788 43704 - Disclosure - Share-based payments - Fair value assumptions (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureShareBasedPaymentsFairValueAssumptionsDetails
2789 Implied Table Table

*

*

 implied:Table
2790 Share-based payments Abstract ifrs-full:DisclosureOfTermsAndConditionsOfSharebasedPaymentArrangementAbstract
2791 Risk-free rate Concept (Percent) For Period wbk:SharebasedPaymentArrangementFairValueAssumptionsRiskFreeRate
2792 Dividend yield Concept (Percent) For Period wbk:SharebasedPaymentArrangementFairValueAssumptionsDividendYield
2793 Volatility rate Concept (Percent) For Period wbk:SharebasedPaymentArrangementFairValueAssumptionsVolatilityRate
2794 43801 - Disclosure - Superannuation commitments (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureSuperannuationCommitmentsDetails
2795 Disclosure of defined benefit plans [table] Table

*

*

 ifrs-full:DisclosureOfDefinedBenefitPlansTable
2796 Defined benefit plans [axis] Axis ifrs-full:DefinedBenefitPlansAxis
2797 Defined benefit plans [member] Member ifrs-full:DefinedBenefitPlansMember
2798 Westpac Group Plan Member wbk:WestpacGroupPlanMember
2799 Westpac New Zealand Superannuation Scheme Member wbk:WestpacNewZealandSuperannuationSchemeMember
2800 Staff Superannuation Scheme Member wbk:StaffSuperannuationSchemeMember
2801 Superannuation commitments LineItems ifrs-full:DisclosureOfDefinedBenefitPlansLineItems
2802 Funding surplus Concept (Monetary) For Period Debit wbk:DefinedBenefitPlanFundingSurplus
2803 Percentage of contribution on member's salary Concept (Percent) For Period wbk:PercentageOfContributionOnMembersSalary
2804 Contribution per year Concept (Monetary) For Period Credit wbk:DefinedBenefitPlanContributionPerYear
2805 43802 - Disclosure - Superannuation commitments - Expense recognised (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureSuperannuationCommitmentsExpenseRecognisedDetails
2806 Disclosure of defined benefit plans [table] Table

*

*

 ifrs-full:DisclosureOfDefinedBenefitPlansTable
2807 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
2808 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
2809 Parent Entity Member us-gaap:ParentCompanyMember
2810 Superannuation commitments LineItems ifrs-full:DisclosureOfDefinedBenefitPlansLineItems
2811 Employer contributions Concept (Monetary) For Period Credit ifrs-full:EmployerContributions
2812 Member contributions Concept (Monetary) For Period Credit ifrs-full:EmployeeContributions
2813 Expected contribution from the employer Concept (Monetary) For Period Credit ifrs-full:EstimateOfContributionsExpectedToBePaidToPlan
2814 Current service cost Concept (Monetary) For Period Debit wbk:DefinedBenefitPlansServiceCost
2815 Net interest cost on net benefit liability Concept (Monetary) For Period Debit wbk:DefinedBenefitPlansNetInterestCost
2816 Total defined benefit expense Concept (Monetary) For Period Debit ifrs-full:PostemploymentBenefitExpenseDefinedBenefitPlans
2817 Defined benefit balances recognised Abstract ifrs-full:SurplusDeficitInPlanAbstract
2818 Benefit obligation at end of the year Concept (Monetary) As Of Credit ifrs-full:DefinedBenefitObligationAtPresentValue
2819 Fair value of plan assets at end of the year Concept (Monetary) As Of Debit ifrs-full:PlanAssetsAtFairValue
2820 Net surplus/(deficit) Concept (Monetary) As Of Debit ifrs-full:SurplusDeficitInPlan
2821 Defined benefit surplus (Note 27) Concept (Monetary) As Of Debit ifrs-full:RecognisedAssetsDefinedBenefitPlan
2822 Defined benefit deficit (Note 29) Concept (Monetary) As Of Credit ifrs-full:RecognisedLiabilitiesDefinedBenefitPlan
2823 Average duration of the defined benefit obligation Concept (Decimal) For Period ifrs-full:WeightedAverageDurationOfDefinedBenefitObligation
2824 43803 - Disclosure - Superannuation commitments - Significant assumptions (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureSuperannuationCommitmentsSignificantAssumptionsDetails
2825 Disclosure of defined benefit plans [table] Table

*

*

 ifrs-full:DisclosureOfDefinedBenefitPlansTable
2826 Geographical [Axis] Axis us-gaap:StatementGeographicalAxis
2827 Geographical [Domain] Member us-gaap:SegmentGeographicalDomain
2828 Australia Member ifrs-full:CountryOfDomicileMember
2829 Overseas Member ifrs-full:ForeignCountriesMember
2830 Range [axis] Axis ifrs-full:RangeAxis
2831 Ranges [member] Member ifrs-full:RangesMember
2832 Maximum Member ifrs-full:TopOfRangeMember
2833 Minimum Member ifrs-full:BottomOfRangeMember
2834 Superannuation commitments LineItems ifrs-full:DisclosureOfDefinedBenefitPlansLineItems
2835 Discount rate Concept (Percent) As Of ifrs-full:ActuarialAssumptionOfDiscountRates
2836 Expected salary increase Concept (Percent) As Of ifrs-full:ActuarialAssumptionOfExpectedRatesOfSalaryIncreases
2837 Expected inflation Concept (Percent) As Of ifrs-full:ActuarialAssumptionOfExpectedRatesOfInflation
2838 Life expectancy of a 60-year-old male Concept (xbrli:durationItemType) For Period wbk:ActuarialAssumptionOfLifeExpectancyAfterRetirementOfMale
2839 Life expectancy of a 60-year-old female Concept (xbrli:durationItemType) For Period wbk:ActuarialAssumptionOfLifeExpectancyAfterRetirementOfFemale
2840 43804 - Disclosure - Superannuation commitments - Sensitivity to changes in significant assumptions (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureSuperannuationCommitmentsSensitivityToChangesInSignificantAssumptionsDetails
2841 Disclosure of defined benefit plans [table] Table

*

*

 ifrs-full:DisclosureOfDefinedBenefitPlansTable
2842 Actuarial assumptions [axis] Axis ifrs-full:ActuarialAssumptionsAxis
2843 Actuarial assumptions [member] Member ifrs-full:ActuarialAssumptionsMember
2844 Discount rate Member ifrs-full:ActuarialAssumptionOfDiscountRatesMember
2845 annual salary increases Member ifrs-full:ActuarialAssumptionOfExpectedRatesOfSalaryIncreasesMember
2846 inflation rate Member ifrs-full:ActuarialAssumptionOfExpectedRatesOfInflationMember
2847 Expected lifetime Member ifrs-full:ActuarialAssumptionOfLifeExpectancyAfterRetirementMember
2848 Superannuation commitments LineItems ifrs-full:DisclosureOfDefinedBenefitPlansLineItems
2849 Increase in actuarial assumption (as a percent) Concept (Percent) As Of ifrs-full:PercentageOfReasonablyPossibleIncreaseInActuarialAssumption
2850 Decrease in actuarial assumption (as a percent) Concept (Percent) As Of ifrs-full:PercentageOfReasonablyPossibleDecreaseInActuarialAssumption
2851 Increase in actuarial assumption, Increase (decrease) in the net defined benefit obligation Concept (Monetary) As Of Credit ifrs-full:IncreaseDecreaseInDefinedBenefitObligationDueToReasonablyPossibleIncreaseInActuarialAssumption
2852 Increase in term of life expectancy Concept (xbrli:durationItemType) For Period wbk:DefinedBenefitObligationIncreaseInTermOfLifeExpectancy
2853 43805 - Disclosure - Superannuation commitments - Asset allocation (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureSuperannuationCommitmentsAssetAllocationDetails
2854 Disclosure of defined benefit plans [table] Table

*

*

 ifrs-full:DisclosureOfDefinedBenefitPlansTable
2855 Geographical [Axis] Axis us-gaap:StatementGeographicalAxis
2856 Geographical [Domain] Member us-gaap:SegmentGeographicalDomain
2857 Australia Member ifrs-full:CountryOfDomicileMember
2858 Overseas Member ifrs-full:ForeignCountriesMember
2859 Classes of financial instruments [axis] Axis ifrs-full:ClassesOfFinancialInstrumentsAxis
2860 Financial instruments, class [member] Member ifrs-full:ClassesOfFinancialInstrumentsMember
2861 Cash Member wbk:IfrsCashMember
2862 Equity instruments Member ifrs-full:EquityInvestmentsMember
2863 Debt instruments Member ifrs-full:DebtSecuritiesMember
2864 Property Member wbk:PropertyMember
2865 Other assets Member ifrs-full:OtherAssetsMember
2866 Superannuation commitments LineItems ifrs-full:DisclosureOfDefinedBenefitPlansLineItems
2867 Asset allocation percentage Concept (Percent) As Of wbk:DefinedBenefitPlanPercentageOfPlanAssetAllocation
2868 43901 - Disclosure - Auditor's remuneration (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureAuditorSRemunerationDetails
2869 Disclosure of geographical areas [table] Table

*

*

 ifrs-full:DisclosureOfGeographicalAreasTable
2870 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
2871 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
2872 Parent Entity Member us-gaap:ParentCompanyMember
2873 Counterparties [axis] Axis ifrs-full:CounterpartiesAxis
2874 Counterparties [member] Member ifrs-full:CounterpartiesMember
2875 PwC Australia Member wbk:PricewaterhouseCoopersAustraliaMember
2876 Overseas PwC network firms Member wbk:PricewaterhouseCoopersOverseasMember
2877 Income tax expense LineItems ifrs-full:DisclosureOfGeographicalAreasLineItems
2878 Audit fees Concept (Monetary) For Period Debit ifrs-full:AuditorsRemunerationForAuditServices
2879 Audit-related fees Concept (Monetary) For Period Debit wbk:AuditorsRemunerationForAuditRelatedServices
2880 Total audit and audit-related fees Concept (Monetary) For Period Debit wbk:AuditorsRemunerationForAuditAndAuditRelatedServices
2881 Tax fees Concept (Monetary) For Period Debit ifrs-full:AuditorsRemunerationForTaxServices
2882 Other fees Concept (Monetary) For Period Debit ifrs-full:AuditorsRemunerationForOtherServices
2883 Total audit and non-audit fees Concept (Monetary) For Period Debit ifrs-full:AuditorsRemuneration
2884 Fees received by auditor from various entities related to Westpac but not consolidated Concept (Monetary) For Period Debit wbk:AuditorsRemunerationFromRelatedParties
2885 44001 - Disclosure - Related party disclosures - Superannuation plans (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureRelatedPartyDisclosuresSuperannuationPlansDetails
2886 Implied Table Table

*

*

 implied:Table
2887 Related party disclosures Abstract ifrs-full:DisclosureOfTransactionsBetweenRelatedPartiesAbstract
2888 Group contributions to defined contribution plans Concept (Monetary) For Period Debit wbk:ContributionsToPlanByEmployerDefinedContributionPlans
2889 Group contributions to defined benefit plans Concept (Monetary) For Period Debit ifrs-full:ContributionsToPlanByEmployerNetDefinedBenefitLiabilityAsset
2890 44002 - Disclosure - Related party disclosures - Remuneration of KMP (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureRelatedPartyDisclosuresRemunerationOfKmpDetails
2891 Disclosure of transactions between related parties [table] Table

*

*

 ifrs-full:DisclosureOfTransactionsBetweenRelatedPartiesTable
2892 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
2893 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
2894 Parent Entity Member us-gaap:ParentCompanyMember
2895 Remuneration of KMP LineItems ifrs-full:DisclosureOfTransactionsBetweenRelatedPartiesLineItems
2896 Short-term Benefits Concept (Monetary) For Period Debit ifrs-full:KeyManagementPersonnelCompensationShorttermEmployeeBenefits
2897 Post Employment Benefits Concept (Monetary) For Period Debit ifrs-full:KeyManagementPersonnelCompensationPostemploymentBenefits
2898 Other Long-term Benefits Concept (Monetary) For Period Debit ifrs-full:KeyManagementPersonnelCompensationOtherLongtermBenefits
2899 Share-based Payments Concept (Monetary) For Period Debit ifrs-full:KeyManagementPersonnelCompensationSharebasedPayment
2900 Total Concept (Monetary) For Period Debit ifrs-full:KeyManagementPersonnelCompensation
2901 44003 - Disclosure - Related party disclosures - Other transactions with KMP (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureRelatedPartyDisclosuresOtherTransactionsWithKmpDetails
2902 Disclosure of transactions between related parties [table] Table

*

*

 ifrs-full:DisclosureOfTransactionsBetweenRelatedPartiesTable
2903 Categories of related parties [axis] Axis ifrs-full:CategoriesOfRelatedPartiesAxis
2904 Entity's total for related parties [member] Member ifrs-full:EntitysTotalForRelatedPartiesMember
2905 Key management personnel Member ifrs-full:KeyManagementPersonnelOfEntityOrParentMember
2906 Remuneration of KMP LineItems ifrs-full:DisclosureOfTransactionsBetweenRelatedPartiesLineItems
2907 Interest Payable for the Year Concept (Monetary) For Period Credit wbk:RevenueFromInterestRelatedPartyTransactions
2908 Closing Loan Balance Concept (Monetary) As Of Debit ifrs-full:AmountsReceivableRelatedPartyTransactions
2909 Number of KMP with Loans Concept (Integer) For Period wbk:NumberOfKeyManagementPersonnelWithLoans
2910 44004 - Disclosure - Related party disclosures - Options and share rights holdings (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureRelatedPartyDisclosuresOptionsAndShareRightsHoldingsDetails
2911 Disclosure of transactions between related parties [table] Table

*

*

 ifrs-full:DisclosureOfTransactionsBetweenRelatedPartiesTable
2912 Categories of related parties [axis] Axis ifrs-full:CategoriesOfRelatedPartiesAxis
2913 Entity's total for related parties [member] Member ifrs-full:EntitysTotalForRelatedPartiesMember
2914 Key management personnel Member ifrs-full:KeyManagementPersonnelOfEntityOrParentMember
2915 Brian Hartzer Member wbk:BrianHartzerMember
2916 Lyn Cobley Member wbk:LynCobleyMember
2917 Brad Cooper Member wbk:BradCooperMember
2918 David Curran Member wbk:DavidCurranMember
2919 George Frazis Member wbk:GeorgeFrazisMember
2920 Peter King Member wbk:PeterKingMember
2921 David Lees Member wbk:DavidLeesMember
2922 Rebecca Lim Member wbk:RebeccaLimMember
2923 David Linberg Member wbk:DavidLinbergMember
2924 Carolyn McCann Member wbk:CarolynMccannMember
2925 David McLean Member wbk:DavidMcleanMember
2926 Christine Parker Member wbk:ChristineParkerMember
2927 Gary Thursby Member wbk:GaryThursbyMember
2928 Alexandra Holcomb Member wbk:AlexandraHolcombMember
2929 Options and share rights holdings LineItems ifrs-full:DisclosureOfTransactionsBetweenRelatedPartiesLineItems
2930 Number of Share Rights Concept (Decimal) As Of ifrs-full:NumberOfOtherEquityInstrumentsOutstandingInSharebasedPaymentArrangement
2931 Number of Options Concept (Decimal) As Of ifrs-full:NumberOfOutstandingShareOptions
2932 Exercise Price of Options Concept (Monetary) As Of ifrs-full:ExercisePriceOfOutstandingShareOptions
2933 44101 - Disclosure - Notes to the cash flow statements - Reconciliation of operating activities (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureNotesToCashFlowStatementsReconciliationOfOperatingActivitiesDetails
2934 Condensed Financial Statements [Table] Table

*

*

 us-gaap:ScheduleOfCondensedFinancialStatementsTable
2935 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
2936 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
2937 Parent Entity Member us-gaap:ParentCompanyMember
2938 Condensed financial statements LineItems us-gaap:CondensedFinancialStatementsCaptionsLineItems
2939 Net profit for the year Concept (Monetary) For Period Credit ifrs-full:ProfitLoss
2940 Adjustments: Abstract ifrs-full:AdjustmentsForReconcileProfitLossAbstract
2941 Depreciation, amortisation and impairment Concept (Monetary) For Period Debit ifrs-full:AdjustmentsForDepreciationAndAmortisationExpenseAndImpairmentLossReversalOfImpairmentLossRecognisedInProfitOrLoss
2942 Impairment charges Concept (Monetary) For Period Debit ifrs-full:AdjustmentsForImpairmentLossReversalOfImpairmentLossRecognisedInProfitOrLossLoansAndAdvances
2943 Net (decrease)/increase in current and deferred tax Concept (Monetary) For Period Debit ifrs-full:AdjustmentsForIncomeTaxExpense
2944 (Increase)/decrease in accrued interest receivable Concept (Monetary) For Period Credit ifrs-full:AdjustmentsForInterestIncome
2945 (Decrease)/increase in accrued interest payable Concept (Monetary) For Period Debit ifrs-full:AdjustmentsForInterestExpense
2946 (Decrease)/increase in provisions Concept (Monetary) For Period Debit ifrs-full:AdjustmentsForProvisions
2947 Other non-cash items Concept (Monetary) For Period Debit ifrs-full:OtherAdjustmentsForNoncashItems
2948 Cash flows from operating activities before changes in operating assets and liabilities Concept (Monetary) For Period ifrs-full:CashFlowsFromUsedInOperationsBeforeChangesInWorkingCapital
2949 Net (increase)/decrease in derivative financial instruments Concept (Monetary) For Period Debit wbk:AdjustmentsForDecreaseIncreaseInDerivativeFinancialInstruments
2950 Net (increase)/decrease in life insurance assets and liabilities Concept (Monetary) For Period Debit wbk:AdjustmentsForDecreaseIncreaseInLifeInsuranceAssetsAndLiabilities
2951 (Increase)/decrease in other operating assets: Abstract wbk:NetIncreaseDecreaseInAssetsOperatingActivitiesAbstract
2952 Trading securities and financial assets designated at fair value Concept (Monetary) For Period Debit wbk:AdjustmentsForDecreaseIncreaseInFinancialAssetsAtFairValueThroughProfitOrLoss
2953 Loans Concept (Monetary) For Period Debit wbk:AdjustmentsForDecreaseIncreaseInLoansAndReceivables
2954 Receivables due from other financial institutions Concept (Monetary) For Period Debit wbk:AdjustmentsForDecreaseIncreaseInReceivablesDueFromOtherFinancialInstitutions
2955 Regulatory deposits with central banks overseas Concept (Monetary) For Period Debit wbk:AdjustmentsForDecreaseIncreaseInMandatoryReserveDepositsAtCentralBanks
2956 Other assets Concept (Monetary) For Period Debit ifrs-full:AdjustmentsForDecreaseIncreaseInOtherAssets
2957 (Decrease)/increase in other operating liabilities: Abstract wbk:NetIncreaseDecreaseInLiabilitiesOperatingActivitiesAbstract
2958 Other financial liabilities at fair value through income statement Concept (Monetary) For Period Debit wbk:AdjustmentsForIncreaseDecreaseInFinancialLiabilitiesAtFairValueThroughProfitOrLoss
2959 Deposits and other borrowings Concept (Monetary) For Period Debit wbk:AdjustmentsForIncreaseDecreaseInDepositsAndOtherBorrowings
2960 Payables due to other financial institutions Concept (Monetary) For Period Debit wbk:AdjustmentsForIncreaseDecreaseInPayablesDueToOtherFinancialInstitutions
2961 Other liabilities Concept (Monetary) For Period Debit ifrs-full:AdjustmentsForIncreaseDecreaseInOtherLiabilities
2962 Net cash provided by/(used in) operating activities Concept (Monetary) For Period ifrs-full:CashFlowsFromUsedInOperatingActivities
2963 44102 - Disclosure - Notes to the cash flow statements - Assets and liabilities over which control ceased (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureNotesToCashFlowStatementsAssetsAndLiabilitiesOverWhichControlCeasedDetails
2964 Noncurrent Assets Or Disposal Groups Classified As Held For Sale [Table] Table

*

*

 wbk:NoncurrentAssetsOrDisposalGroupsClassifiedAsHeldForSaleTable
2965 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
2966 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
2967 Parent Entity Member us-gaap:ParentCompanyMember
2968 Assets and liabilities classified as held for sale [axis] Axis ifrs-full:AssetsAndLiabilitiesClassifiedAsHeldForSaleAxis
2969 Assets and liabilities not classified as held for sale [member] Member ifrs-full:AssetsAndLiabilitiesNotClassifiedAsHeldForSaleMember
2970 Assets and liabilities over which control ceased Member ifrs-full:AssetsAndLiabilitiesClassifiedAsHeldForSaleMember
2971 Noncurrent Assets Or Disposal Groups Classified As Held For Sale [Line Items] LineItems wbk:NoncurrentAssetsOrDisposalGroupsClassifiedAsHeldForSaleLineItems
2972 Assets: Abstract ifrs-full:AssetsAbstract
2973 Cash and balances with central banks Concept (Monetary) As Of Debit ifrs-full:CashAndBankBalancesAtCentralBanks
2974 Available-for-sale securities Concept (Monetary) As Of Debit ifrs-full:FinancialAssetsAvailableforsale
2975 Loans Concept (Monetary) As Of Debit ifrs-full:LoansAndReceivables
2976 Regulatory deposits with central banks overseas Concept (Monetary) As Of Debit ifrs-full:MandatoryReserveDepositsAtCentralBanks
2977 Property and equipment Concept (Monetary) As Of Debit ifrs-full:PropertyPlantAndEquipment
2978 Deferred tax assets Concept (Monetary) As Of Debit ifrs-full:NetDeferredTaxAssets
2979 Intangible assets Concept (Monetary) As Of Debit ifrs-full:IntangibleAssetsAndGoodwill
2980 Other assets Concept (Monetary) As Of Debit ifrs-full:OtherAssets
2981 Total assets Concept (Monetary) As Of Debit ifrs-full:Assets
2982 Liabilities: Abstract ifrs-full:LiabilitiesAbstract
2983 Deposits and other borrowings Concept (Monetary) As Of Credit wbk:DepositsAndOtherBorrowings
2984 Current tax liabilities Concept (Monetary) As Of Credit ifrs-full:CurrentTaxLiabilities
2985 Provisions Concept (Monetary) As Of Credit ifrs-full:Provisions
2986 Other liabilities Concept (Monetary) As Of Credit ifrs-full:OtherLiabilities
2987 Total liabilities Concept (Monetary) As Of Credit ifrs-full:Liabilities
2988 Total equity attributable to owners of Westpac Banking Corporation Concept (Monetary) As Of Credit ifrs-full:EquityAttributableToOwnersOfParent
2989 Cash proceeds (net of transaction costs) Concept (Monetary) For Period Debit ifrs-full:ProceedsFromDisposalOfNoncurrentAssetsOrDisposalGroupsClassifiedAsHeldForSaleAndDiscontinuedOperations
2990 Total consideration Concept (Monetary) For Period Debit wbk:TotalConsiderationFromDisposalOfNonCurrentAssetsOrDisposalGroupsClassifiedAsHeldForSaleAndDiscontinuedOperations
2991 Reserves recycled to income statement Concept (Monetary) For Period Credit wbk:ReservesReclassifiedToProfitOrLossOnDisposalOfNonCurrentAssetsOrDisposalGroupsClassifiedAsHeldForSaleAndDiscontinuedOperations
2992 Gain/(loss) on disposal Concept (Monetary) For Period Credit ifrs-full:GainsLossesOnDisposalsOfNoncurrentAssets
2993 Reconciliation of cash proceeds from disposal Abstract wbk:ReconciliationOfCashProceedsFromDisposalAbstract
2994 Cash proceeds (net of transaction costs) Concept (Monetary) For Period Debit ifrs-full:ProceedsFromDisposalOfNoncurrentAssetsOrDisposalGroupsClassifiedAsHeldForSaleAndDiscontinuedOperations
2995 Less: Cash deconsolidated Concept (Monetary) For Period Credit wbk:CashDeconsolidatedOnDisposalOfNonCurrentAssetsOrDisposalGroupsClassifiedAsHeldForSaleAndDiscontinuedOperations
2996 Cash consideration (paid)/received (net of transaction costs and cash held) Concept (Monetary) For Period Debit wbk:ProceedsFromDisposalOfNonCurrentAssetsOrDisposalGroupsClassifiedAsHeldForSaleAndDiscontinuedOperationsNetOfCashDeconsolidated
2997 44103 - Disclosure - Notes to the cash flow statements - Non-cash financing activities and restricted cash (Details) Network

*

*

 http://www.westpac.com.au/role/DisclosureNotesToCashFlowStatementsNonCashFinancingActivitiesAndRestrictedCashDetails
2998 Supplemental Cash Flow Statement Disclosures [Table] Table

*

*

 wbk:SupplementalCashFlowStatementDisclosuresTable
2999 Consolidated Entities [Axis] Axis us-gaap:ConsolidatedEntitiesAxis
3000 Consolidated Entities [Domain] Member us-gaap:ConsolidatedEntitiesDomain
3001 Parent Entity Member us-gaap:ParentCompanyMember
3002 Loan Capital Conversion Description [Axis] Axis wbk:LoanCapitalConversionDescriptionAxis
3003 Loan Capital Conversion Description [Domain] Member wbk:LoanCapitalConversionDescriptionDomain
3004 Westpac CPS converted to Westpac Capital Notes Member wbk:ConversionOfConvertiblePreferenceSharesIntoCapitalNotesMember
3005 Westpac CPS converted to ordinary shares Member wbk:ConversionOfConvertiblePreferenceSharesIntoOrdinarySharesMember
3006 Supplemental Cash Flow Statement Disclosures [Line Items] LineItems wbk:SupplementalCashFlowStatementDisclosuresLineItems
3007 Non-cash financing activities Abstract wbk:NonCashFinancingActivitiesAbstract
3008 Shares issued under the dividend reinvestment plan Concept (Monetary) For Period Credit wbk:IfrsStockIssuedDuringPeriodValueDividendReinvestmentPlan
3009 Shares issued from the conversion of Westpac CPS Concept (Monetary) For Period Credit wbk:IfrsStockIssuedDuringPeriodValueConversionOfConvertibleSecurities
3010 Number of Westpac CPS converted Concept (Shares) For Period wbk:ConversionOfLoanCapitalSharesConverted
3011 Value of Westpac CPS converted Concept (Monetary) For Period Debit wbk:ConversionOfLoanCapitalAmountConverted
3012 Value per share of Westpac CPS transferred to nominated party prior to conversion Concept (Share) For Period wbk:ConversionOfLoanCapitalPerShareAmountTransferredToNominatedParty
3013 Shares issued on conversion of Westpac CPS Concept (Shares) For Period wbk:IfrsStockIssuedDuringPeriodSharesConversionOfConvertibleSecurities
3014 Restricted cash Concept (Monetary) As Of Debit ifrs-full:RestrictedCashAndCashEquivalents

*

*