HONDA MOTOR CO LTD (SEC Filing Page | XBRL Cloud Viewer | XBRL Instance)

Line	Label	Object Class	Period Type	Balance	Report ElementName
1	1001 - Document - Document and Entity Information	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DocumentandEntityInformation
2	Implied Table	Table	*	*	implied:Table
3	Document - Document and Entity Information [Abstract]	Abstract			hmc:DocumentandEntityInformationAbstract
4	Document Type	Concept (Submission Type)	For Period		dei:DocumentType
5	Amendment Flag	Concept (Yes/No)	For Period		dei:AmendmentFlag
6	Document Period End Date	Concept (Date)	For Period		dei:DocumentPeriodEndDate
7	Document Fiscal Year Focus	Concept (Year)	For Period		dei:DocumentFiscalYearFocus
8	Document Fiscal Period Focus	Concept (Fiscal Period)	For Period		dei:DocumentFiscalPeriodFocus
9	Trading Symbol	Concept (Text/String)	For Period		dei:TradingSymbol
10	Entity Registrant Name	Concept (Text/String)	For Period		dei:EntityRegistrantName
11	Entity Central Index Key	Concept (CIK Number)	For Period		dei:EntityCentralIndexKey
12	Current Fiscal Year End Date	Concept (Month/Day)	For Period		dei:CurrentFiscalYearEndDate
13	Entity Well-known Seasoned Issuer	Concept (Yes/No)	For Period		dei:EntityWellKnownSeasonedIssuer
14	Entity Current Reporting Status	Concept (Yes/No)	For Period		dei:EntityCurrentReportingStatus
15	Entity Filer Category	Concept (Filer Category)	For Period		dei:EntityFilerCategory
16	Entity Common Stock, Shares Outstanding	Concept (Shares)	As Of		dei:EntityCommonStockSharesOutstanding
17	1003 - Statement - Consolidated Statements of Financial Position	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/StatementOfFinancialPositionCurrentNonCurrent-210000
18	Statement [Table]	Table	*	*	us-gaap:StatementTable
19	Property, plant and equipment by operating lease status [axis]	Axis			ifrs-full:PropertyPlantAndEquipmentByOperatingLeaseStatusAxis
20	Property, plant and equipment by operating lease status [member]	Member			ifrs-full:PropertyPlantAndEquipmentByOperatingLeaseStatusMember
21	Equipment on operating leases [member]	Member			ifrs-full:PropertyPlantAndEquipmentSubjectToOperatingLeasesMember
22	Property, plant and equipment [member]	Member			ifrs-full:PropertyPlantAndEquipmentNotSubjectToOperatingLeasesMember
23	Statement [Line Items]	LineItems			us-gaap:StatementLineItems
24	Assets	Abstract			ifrs-full:AssetsAbstract
25	Current assets:	Abstract			ifrs-full:CurrentAssetsAbstract
26	Cash and cash equivalents	Concept (Monetary)	As Of	Debit	ifrs-full:CashAndCashEquivalents
27	Trade receivables	Concept (Monetary)	As Of	Debit	ifrs-full:CurrentTradeReceivables
28	Receivables from financial services	Concept (Monetary)	As Of	Debit	ifrs-full:CurrentLoansAndReceivables
29	Other financial assets	Concept (Monetary)	As Of	Debit	ifrs-full:OtherCurrentFinancialAssets
30	Inventories	Concept (Monetary)	As Of	Debit	ifrs-full:Inventories
31	Other current assets	Concept (Monetary)	As Of	Debit	ifrs-full:OtherCurrentNonfinancialAssets
32	Total current assets	Concept (Monetary)	As Of	Debit	ifrs-full:CurrentAssets
33	Non-current assets:	Abstract			ifrs-full:NoncurrentAssetsAbstract
34	Investments accounted for using the equity method	Concept (Monetary)	As Of	Debit	ifrs-full:InvestmentAccountedForUsingEquityMethod
35	Receivables from financial services	Concept (Monetary)	As Of	Debit	ifrs-full:NoncurrentLoansAndReceivables
36	Other financial assets	Concept (Monetary)	As Of	Debit	ifrs-full:OtherNoncurrentFinancialAssets
37	Property, plant and equipment	Concept (Monetary)	As Of	Debit	ifrs-full:PropertyPlantAndEquipment
38	Intangible assets	Concept (Monetary)	As Of	Debit	ifrs-full:IntangibleAssetsAndGoodwill
39	Deferred tax assets	Concept (Monetary)	As Of	Debit	ifrs-full:DeferredTaxAssets
40	Other non-current assets	Concept (Monetary)	As Of	Debit	ifrs-full:OtherNoncurrentNonfinancialAssets
41	Total non-current assets	Concept (Monetary)	As Of	Debit	ifrs-full:NoncurrentAssets
42	Total assets	Concept (Monetary)	As Of	Debit	ifrs-full:Assets
43	Liabilities and Equity	Abstract			ifrs-full:EquityAndLiabilitiesAbstract
44	Current liabilities:	Abstract			ifrs-full:CurrentLiabilitiesAbstract
45	Trade payables	Concept (Monetary)	As Of	Credit	ifrs-full:TradeAndOtherCurrentPayablesToTradeSuppliers
46	Financing liabilities	Concept (Monetary)	As Of	Credit	ifrs-full:CurrentBorrowingsAndCurrentPortionOfNoncurrentBorrowings
47	Accrued expenses	Concept (Monetary)	As Of	Credit	ifrs-full:AccrualsClassifiedAsCurrent
48	Other financial liabilities	Concept (Monetary)	As Of	Credit	ifrs-full:OtherCurrentFinancialLiabilities
49	Income taxes payable	Concept (Monetary)	As Of	Credit	ifrs-full:CurrentTaxLiabilitiesCurrent
50	Provisions	Concept (Monetary)	As Of	Credit	ifrs-full:OtherShorttermProvisions
51	Other current liabilities	Concept (Monetary)	As Of	Credit	ifrs-full:OtherCurrentNonfinancialLiabilities
52	Total current liabilities	Concept (Monetary)	As Of	Credit	ifrs-full:CurrentLiabilities
53	Non-current liabilities:	Abstract			ifrs-full:NoncurrentLiabilitiesAbstract
54	Financing liabilities	Concept (Monetary)	As Of	Credit	ifrs-full:LongtermBorrowings
55	Other financial liabilities	Concept (Monetary)	As Of	Credit	ifrs-full:OtherNoncurrentFinancialLiabilities
56	Retirement benefit liabilities	Concept (Monetary)	As Of	Credit	ifrs-full:NoncurrentRecognisedLiabilitiesDefinedBenefitPlan
57	Provisions	Concept (Monetary)	As Of	Credit	ifrs-full:OtherLongtermProvisions
58	Deferred tax liabilities	Concept (Monetary)	As Of	Credit	ifrs-full:DeferredTaxLiabilities
59	Other non-current liabilities	Concept (Monetary)	As Of	Credit	ifrs-full:OtherNoncurrentNonfinancialLiabilities
60	Total non-current liabilities	Concept (Monetary)	As Of	Credit	ifrs-full:NoncurrentLiabilities
61	Total liabilities	Concept (Monetary)	As Of	Credit	ifrs-full:Liabilities
62	Equity:	Abstract			ifrs-full:EquityAbstract
63	Common stock	Concept (Monetary)	As Of	Credit	ifrs-full:IssuedCapital
64	Capital surplus	Concept (Monetary)	As Of	Credit	ifrs-full:AdditionalPaidinCapital
65	Treasury stock	Concept (Monetary)	As Of	Debit	ifrs-full:TreasuryShares
66	Retained earnings	Concept (Monetary)	As Of	Credit	ifrs-full:RetainedEarnings
67	Other components of equity	Concept (Monetary)	As Of	Credit	ifrs-full:OtherReserves
68	Equity attributable to owners of the parent	Concept (Monetary)	As Of	Credit	ifrs-full:EquityAttributableToOwnersOfParent
69	Non-controlling interests	Concept (Monetary)	As Of	Credit	ifrs-full:NoncontrollingInterests
70	Total equity	Concept (Monetary)	As Of	Credit	ifrs-full:Equity
71	Total liabilities and equity	Concept (Monetary)	As Of	Credit	ifrs-full:EquityAndLiabilities
72	1004 - Statement - Consolidated Statements of Income	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/StatementOfComprehensiveIncomeProfitOrLossByNatureOfExpense-320000
73	Implied Table	Table	*	*	implied:Table
74	Profit or loss [abstract]	Abstract			ifrs-full:IncomeStatementAbstract
75	Sales revenue	Concept (Monetary)	For Period	Credit	ifrs-full:Revenue
76	Operating costs and expenses:	Abstract			hmc:OperatingCostAndExpensesAbstract
77	Cost of sales	Concept (Monetary)	For Period	Debit	ifrs-full:CostOfSales
78	Selling, general and administrative	Concept (Monetary)	For Period	Debit	ifrs-full:SellingGeneralAndAdministrativeExpense
79	Research and development	Concept (Monetary)	For Period	Debit	ifrs-full:ResearchAndDevelopmentExpense
80	Total operating costs and expenses	Concept (Monetary)	For Period	Debit	ifrs-full:OperatingExpense
81	Operating profit	Concept (Monetary)	For Period	Credit	ifrs-full:ProfitLossFromOperatingActivities
82	Share of profit of investments accounted for using the equity method	Concept (Monetary)	For Period	Credit	ifrs-full:ShareOfProfitLossOfAssociatesAndJointVenturesAccountedForUsingEquityMethod
83	Finance income and finance costs:	Abstract			hmc:FinanceIncomeAndFinanceCostsAbstract
84	Interest income	Concept (Monetary)	For Period	Credit	ifrs-full:FinanceIncome
85	Interest expense	Concept (Monetary)	For Period	Debit	ifrs-full:InterestExpense
86	Other, net	Concept (Monetary)	For Period	Credit	ifrs-full:OtherFinanceIncomeCost
87	Total finance income and finance costs	Concept (Monetary)	For Period	Credit	ifrs-full:FinanceIncomeCost
88	Profit before income taxes	Concept (Monetary)	For Period	Credit	ifrs-full:ProfitLossBeforeTax
89	Income tax expense	Concept (Monetary)	For Period	Debit	ifrs-full:IncomeTaxExpenseContinuingOperations
90	Profit for the year	Concept (Monetary)	For Period	Credit	ifrs-full:ProfitLoss
91	Profit for the year attributable to:	Abstract			ifrs-full:ProfitLossAttributableToAbstract
92	Owners of the parent	Concept (Monetary)	For Period	Credit	ifrs-full:ProfitLossAttributableToOwnersOfParent
93	Non-controlling interests	Concept (Monetary)	For Period	Credit	ifrs-full:ProfitLossAttributableToNoncontrollingInterests
94	Profit for the year	Concept (Monetary)	For Period	Credit	ifrs-full:ProfitLoss
95	Earnings per share attributable to owners of the parent	Abstract			ifrs-full:BasicAndDilutedEarningsPerShareAbstract
96	Basic and diluted	Concept (Share)	For Period		ifrs-full:BasicAndDilutedEarningsLossPerShare
97	1005 - Statement - Consolidated Statements of Comprehensive Income	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/StatementOfComprehensiveIncomeOCIComponentsPresentedNetOfTax-410000
98	Implied Table	Table	*	*	implied:Table
99	Statement of comprehensive income [abstract]	Abstract			ifrs-full:StatementOfComprehensiveIncomeAbstract
100	Profit for the year	Concept (Monetary)	For Period	Credit	ifrs-full:ProfitLoss
101	Other comprehensive income, net of tax:	Abstract			ifrs-full:OtherComprehensiveIncomeAbstract
102	Items that will not be reclassified to profit or loss	Abstract			ifrs-full:ComponentsOfOtherComprehensiveIncomeThatWillNotBeReclassifiedToProfitOrLossNetOfTaxAbstract
103	Remeasurements of defined benefit plans	Concept (Monetary)	For Period	Credit	ifrs-full:OtherComprehensiveIncomeNetOfTaxGainsLossesOnRemeasurementsOfDefinedBenefitPlans
104	Net changes in revaluation of financial assets measured at fair value through other comprehensive income	Concept (Monetary)	For Period	Credit	ifrs-full:OtherComprehensiveIncomeNetOfTaxGainsLossesFromInvestmentsInEquityInstruments
105	Share of other comprehensive income of investments accounted for using the equity method	Concept (Monetary)	For Period	Credit	ifrs-full:ShareOfOtherComprehensiveIncomeOfAssociatesAndJointVenturesAccountedForUsingEquityMethodThatWillNotBeReclassifiedToProfitOrLossNetOfTax
106	Items that may be reclassified subsequently to profit or loss	Abstract			ifrs-full:ComponentsOfOtherComprehensiveIncomeThatWillBeReclassifiedToProfitOrLossNetOfTaxAbstract
107	Exchange differences on translating foreign operations	Concept (Monetary)	For Period	Credit	ifrs-full:OtherComprehensiveIncomeNetOfTaxExchangeDifferencesOnTranslation
108	Share of other comprehensive income of investments accounted for using the equity method	Concept (Monetary)	For Period	Credit	ifrs-full:ShareOfOtherComprehensiveIncomeOfAssociatesAndJointVenturesAccountedForUsingEquityMethodThatWillBeReclassifiedToProfitOrLossNetOfTax
109	Total other comprehensive income, net of tax	Concept (Monetary)	For Period	Credit	ifrs-full:OtherComprehensiveIncome
110	Comprehensive income for the year	Concept (Monetary)	For Period	Credit	ifrs-full:ComprehensiveIncome
111	Comprehensive income for the year attributable to:	Abstract			ifrs-full:ComprehensiveIncomeAttributableToAbstract
112	Owners of the parent	Concept (Monetary)	For Period	Credit	ifrs-full:ComprehensiveIncomeAttributableToOwnersOfParent
113	Non-controlling interests	Concept (Monetary)	For Period	Credit	ifrs-full:ComprehensiveIncomeAttributableToNoncontrollingInterests
114	1006 - Statement - Consolidated Statements of Changes in Equity	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/StatementOfChangesInEquity-610000
115	Statement of changes in equity [table]	Table	*	*	ifrs-full:StatementOfChangesInEquityTable
116	Components of equity [axis]	Axis			ifrs-full:ComponentsOfEquityAxis
117	Equity [member]	Member			ifrs-full:EquityMember
118	Common stock [Member]	Member			ifrs-full:IssuedCapitalMember
119	Capital surplus [Member]	Member			ifrs-full:AdditionalPaidinCapitalMember
120	Treasury stock [member]	Member			ifrs-full:TreasurySharesMember
121	Retained earnings [Member]	Member			ifrs-full:RetainedEarningsMember
122	Other components of equity [member]	Member			ifrs-full:OtherReservesMember
123	Equity attributable to owners of the parent [Member]	Member			ifrs-full:EquityAttributableToOwnersOfParentMember
124	Non-controlling interests [Member]	Member			ifrs-full:NoncontrollingInterestsMember
125	Statement of changes in equity [line items]	LineItems			ifrs-full:StatementOfChangesInEquityLineItems
126	Beginning balance	Concept (Monetary)	As Of	Credit	ifrs-full:Equity
127	Comprehensive income for the year	Abstract			ifrs-full:ComprehensiveIncomeAbstract
128	Profit for the year	Concept (Monetary)	For Period	Credit	ifrs-full:ProfitLoss
129	Other comprehensive income, net of tax	Concept (Monetary)	For Period	Credit	ifrs-full:OtherComprehensiveIncome
130	Total comprehensive income for the year	Concept (Monetary)	For Period	Credit	ifrs-full:ComprehensiveIncome
131	Reclassification to retained earnings	Concept (Monetary)	For Period	Credit	hmc:IncreaseDecreaseThroughReclassificationToRetainedEarningsEquity
132	Transactions with owners and other	Abstract			hmc:TransactionsWithOwnersAndOtherAbstract
133	Dividends paid	Concept (Monetary)	For Period	Debit	ifrs-full:DividendsPaid
134	Purchases of treasury stock	Concept (Monetary)	For Period	Debit	ifrs-full:PurchaseOfTreasuryShares
135	Disposal of treasury stock	Concept (Monetary)	For Period	Credit	ifrs-full:SaleOrIssueOfTreasuryShares
136	Equity transactions and others	Concept (Monetary)	For Period	Credit	ifrs-full:IncreaseDecreaseThroughTransfersAndOtherChangesEquity
137	Total transactions with owners and other	Concept (Monetary)	For Period	Credit	ifrs-full:IncreaseDecreaseThroughTransactionsWithOwners
138	Ending balance	Concept (Monetary)	As Of	Credit	ifrs-full:Equity
139	1007 - Statement - Consolidated Statements of Cash Flows	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/StatementOfCashFlowsIndirectMethod-520000
140	Implied Table	Table	*	*	implied:Table
141	Statement of cash flows [abstract]	Abstract			ifrs-full:StatementOfCashFlowsAbstract
142	Cash flows from operating activities:	Abstract			ifrs-full:CashFlowsFromUsedInOperatingActivitiesAbstract
143	Profit before income taxes	Concept (Monetary)	For Period	Credit	ifrs-full:ProfitLossBeforeTax
144	Depreciation, amortization and impairment losses excluding equipment on operating leases	Concept (Monetary)	For Period	Debit	ifrs-full:AdjustmentsForDepreciationAndAmortisationExpenseAndImpairmentLossReversalOfImpairmentLossRecognisedInProfitOrLoss
145	Share of profit of investments accounted for using the equity method	Concept (Monetary)	For Period	Credit	ifrs-full:ShareOfProfitLossOfAssociatesAndJointVenturesAccountedForUsingEquityMethod
146	Finance income and finance costs, net	Concept (Monetary)	For Period	Credit	ifrs-full:AdjustmentsForFinanceIncomeCost
147	Interest income and interest costs from financial services, net	Concept (Monetary)	For Period	Credit	hmc:AdjustmentsForInterestIncomeAndInterestCosts
148	Changes in assets and liabilities	Abstract			ifrs-full:AdjustmentsForReconcileProfitLossAbstract
149	Trade receivables	Concept (Monetary)	For Period	Debit	ifrs-full:AdjustmentsForDecreaseIncreaseInTradeAccountReceivable
150	Inventories	Concept (Monetary)	For Period	Debit	ifrs-full:AdjustmentsForDecreaseIncreaseInInventories
151	Trade payables	Concept (Monetary)	For Period	Debit	ifrs-full:AdjustmentsForIncreaseDecreaseInTradeAccountPayable
152	Accrued expenses	Concept (Monetary)	For Period	Debit	hmc:AdjustmentsForIncreaseDecreaseInAccruedExpenses
153	Provisions and retirement benefit liabilities	Concept (Monetary)	For Period	Debit	ifrs-full:AdjustmentsForProvisions
154	Receivables from financial services	Concept (Monetary)	For Period	Debit	ifrs-full:AdjustmentsForDecreaseIncreaseInLoansAndAdvancesToCustomers
155	Equipment on operating leases	Concept (Monetary)	For Period	Debit	hmc:AdjustmentsForDecreaseIncreaseInEquipmentOnOperatingLeases
156	Other assets and liabilities	Concept (Monetary)	For Period	Debit	ifrs-full:OtherAdjustmentsToReconcileProfitLoss
157	Other, net	Concept (Monetary)	For Period	Debit	ifrs-full:OtherInflowsOutflowsOfCashClassifiedAsOperatingActivities
158	Dividends received	Concept (Monetary)	For Period	Debit	ifrs-full:DividendsReceivedClassifiedAsOperatingActivities
159	Interest received	Concept (Monetary)	For Period	Debit	ifrs-full:InterestReceivedClassifiedAsOperatingActivities
160	Interest paid	Concept (Monetary)	For Period	Credit	ifrs-full:InterestPaidClassifiedAsOperatingActivities
161	Income taxes paid, net of refund	Concept (Monetary)	For Period	Credit	ifrs-full:IncomeTaxesPaidRefundClassifiedAsOperatingActivities
162	Net cash provided by operating activities	Concept (Monetary)	For Period		ifrs-full:CashFlowsFromUsedInOperatingActivities
163	Cash flows from investing activities:	Abstract			ifrs-full:CashFlowsFromUsedInInvestingActivitiesAbstract
164	Payments for additions to property, plant and equipment	Concept (Monetary)	For Period	Credit	ifrs-full:PurchaseOfPropertyPlantAndEquipmentClassifiedAsInvestingActivities
165	Payments for additions to and internally developed intangible assets	Concept (Monetary)	For Period	Credit	ifrs-full:PurchaseOfIntangibleAssetsClassifiedAsInvestingActivities
166	Proceeds from sales of property, plant and equipment and intangible assets	Concept (Monetary)	For Period	Debit	ifrs-full:ProceedsFromDisposalsOfPropertyPlantAndEquipmentIntangibleAssetsOtherThanGoodwillInvestmentPropertyAndOtherNoncurrentAssets
167	Payments for acquisitions of subsidiaries, net of cash and cash equivalents acquired	Concept (Monetary)	For Period	Credit	ifrs-full:CashFlowsUsedInObtainingControlOfSubsidiariesOrOtherBusinessesClassifiedAsInvestingActivities
168	Payments for acquisitions of investments accounted for using the equity method	Concept (Monetary)	For Period	Credit	ifrs-full:PurchaseOfInterestsInInvestmentsAccountedForUsingEquityMethod
169	Proceeds from sales of investments accounted for using the equity method	Concept (Monetary)	For Period	Debit	ifrs-full:ProceedsFromSalesOfInvestmentsAccountedForUsingEquityMethod
170	Payments for acquisitions of other financial assets	Concept (Monetary)	For Period	Credit	ifrs-full:PurchaseOfFinancialInstrumentsClassifiedAsInvestingActivities
171	Proceeds from sales and redemptions of other financial assets	Concept (Monetary)	For Period	Debit	ifrs-full:ProceedsFromSalesOrMaturityOfFinancialInstrumentsClassifiedAsInvestingActivities
172	Other, net	Concept (Monetary)	For Period	Debit	ifrs-full:OtherInflowsOutflowsOfCashClassifiedAsInvestingActivities
173	Net cash used in investing activities	Concept (Monetary)	For Period	Debit	ifrs-full:CashFlowsFromUsedInInvestingActivities
174	Cash flows from financing activities:	Abstract			ifrs-full:CashFlowsFromUsedInFinancingActivitiesAbstract
175	Proceeds from short-term financing liabilities	Concept (Monetary)	For Period	Debit	ifrs-full:ProceedsFromCurrentBorrowings
176	Repayments of short-term financing liabilities	Concept (Monetary)	For Period	Credit	ifrs-full:RepaymentsOfCurrentBorrowings
177	Proceeds from long-term financing liabilities	Concept (Monetary)	For Period	Debit	ifrs-full:ProceedsFromNoncurrentBorrowings
178	Repayments of long-term financing liabilities	Concept (Monetary)	For Period	Credit	ifrs-full:RepaymentsOfNoncurrentBorrowings
179	Dividends paid to owners of the parent	Concept (Monetary)	For Period	Credit	ifrs-full:DividendsPaidToEquityHoldersOfParentClassifiedAsFinancingActivities
180	Dividends paid to non-controlling interests	Concept (Monetary)	For Period	Credit	ifrs-full:DividendsPaidToNoncontrollingInterestsClassifiedAsFinancingActivities
181	Purchases and sales of treasury stock, net	Concept (Monetary)	For Period	Credit	ifrs-full:PaymentsToAcquireOrRedeemEntitysShares
182	Other, net	Concept (Monetary)	For Period	Debit	ifrs-full:OtherInflowsOutflowsOfCashClassifiedAsFinancingActivities
183	Net cash provided by (used in) financing activities	Concept (Monetary)	For Period	Debit	ifrs-full:CashFlowsFromUsedInFinancingActivities
184	Effect of exchange rate changes on cash and cash equivalents	Concept (Monetary)	For Period	Debit	ifrs-full:EffectOfExchangeRateChangesOnCashAndCashEquivalents
185	Net change in cash and cash equivalents	Concept (Monetary)	For Period	Debit	ifrs-full:IncreaseDecreaseInCashAndCashEquivalents
186	Cash and cash equivalents at beginning of year	Concept (Monetary)	As Of	Debit	ifrs-full:CashAndCashEquivalents
187	Cash and cash equivalents at end of year	Concept (Monetary)	As Of	Debit	ifrs-full:CashAndCashEquivalents
188	1008 - Disclosure - Reporting Entity	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfReportingEntityInformationExplanatoryTextBlock
189	Implied Table	Table	*	*	implied:Table
190	Text block1 [abstract]	Abstract			hmc:TextBlock1Abstract
191	Reporting Entity	Concept (Text Block (HTML))	For Period		hmc:DisclosureOfReportingEntityInformationExplanatoryTextBlock
192	1009 - Disclosure - Basis of Preparation	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfBasisOfPreparationOfFinancialStatementsExplanatory
193	Implied Table	Table	*	*	implied:Table
194	Text block1 [abstract]	Abstract			hmc:TextBlock1Abstract
195	Basis of Preparation	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfBasisOfPreparationOfFinancialStatementsExplanatory
196	1010 - Disclosure - Significant Accounting Policies	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfSummaryOfSignificantAccountingPoliciesExplanatory
197	Implied Table	Table	*	*	implied:Table
198	Text block1 [abstract]	Abstract			hmc:TextBlock1Abstract
199	Significant Accounting Policies	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfSummaryOfSignificantAccountingPoliciesExplanatory
200	1011 - Disclosure - Segment Information	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfEntitysReportableSegmentsExplanatory
201	Implied Table	Table	*	*	implied:Table
202	Text block1 [abstract]	Abstract			hmc:TextBlock1Abstract
203	Segment Information	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfEntitysReportableSegmentsExplanatory
204	1012 - Disclosure - Cash and Cash Equivalents	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfCashAndCashEquivalentsExplanatory
205	Implied Table	Table	*	*	implied:Table
206	Text block1 [abstract]	Abstract			hmc:TextBlock1Abstract
207	Cash and Cash Equivalents	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfCashAndCashEquivalentsExplanatory
208	1013 - Disclosure - Trade Receivables	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfTradeAndOtherReceivablesExplanatory
209	Implied Table	Table	*	*	implied:Table
210	Text block1 [abstract]	Abstract			hmc:TextBlock1Abstract
211	Trade Receivables	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfTradeAndOtherReceivablesExplanatory
212	1014 - Disclosure - Receivables from Financial Services	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfLoansAndAdvancesToCustomersExplanatory
213	Implied Table	Table	*	*	implied:Table
214	Text block1 [abstract]	Abstract			hmc:TextBlock1Abstract
215	Receivables from Financial Services	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfLoansAndAdvancesToCustomersExplanatory
216	1015 - Disclosure - Other Financial Assets	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfOtherFinancialAssetsExplanatory
217	Implied Table	Table	*	*	implied:Table
218	Text block1 [abstract]	Abstract			hmc:TextBlock1Abstract
219	Other Financial Assets	Concept (Text Block (HTML))	For Period		hmc:DisclosureOfOtherFinancialAssetsExplanatory
220	1016 - Disclosure - Inventories	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfInventoriesExplanatory
221	Implied Table	Table	*	*	implied:Table
222	Text block1 [abstract]	Abstract			hmc:TextBlock1Abstract
223	Inventories	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfInventoriesExplanatory
224	1017 - Disclosure - Investments Accounted for Using the Equity Method	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfInvestmentsAccountedForUsingEquityMethodExplanatory
225	Implied Table	Table	*	*	implied:Table
226	Text block1 [abstract]	Abstract			hmc:TextBlock1Abstract
227	Investments Accounted for Using the Equity Method	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfInvestmentsAccountedForUsingEquityMethodExplanatory
228	1018 - Disclosure - Property, Plant and Equipment	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfPropertyPlantAndEquipmentExplanatory
229	Statement [Table]	Table	*	*	us-gaap:StatementTable
230	Property, plant and equipment by operating lease status [axis]	Axis			ifrs-full:PropertyPlantAndEquipmentByOperatingLeaseStatusAxis
231	Property, plant and equipment by operating lease status [member]	Member			ifrs-full:PropertyPlantAndEquipmentByOperatingLeaseStatusMember
232	Equipment on operating leases [member]	Member			ifrs-full:PropertyPlantAndEquipmentSubjectToOperatingLeasesMember
233	Property, plant and equipment [member]	Member			ifrs-full:PropertyPlantAndEquipmentNotSubjectToOperatingLeasesMember
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235	Property, Plant and Equipment	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfPropertyPlantAndEquipmentExplanatory
236	1019 - Disclosure - Intangible Assets	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfIntangibleAssetsExplanatory
237	Implied Table	Table	*	*	implied:Table
238	Text block1 [abstract]	Abstract			hmc:TextBlock1Abstract
239	Intangible Assets	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfIntangibleAssetsExplanatory
240	1020 - Disclosure - Trade Payables	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfTradeAndOtherPayablesExplanatory
241	Implied Table	Table	*	*	implied:Table
242	Text block1 [abstract]	Abstract			hmc:TextBlock1Abstract
243	Trade Payables	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfTradeAndOtherPayablesExplanatory
244	1021 - Disclosure - Financing Liabilities	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfBorrowingsExplanatory
245	Implied Table	Table	*	*	implied:Table
246	Text block1 [abstract]	Abstract			hmc:TextBlock1Abstract
247	Financing Liabilities	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfBorrowingsExplanatory
248	1022 - Disclosure - Other Financial Liabilities	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfOtherFinancialLiabilitiesExplanatory
249	Implied Table	Table	*	*	implied:Table
250	Text block1 [abstract]	Abstract			hmc:TextBlock1Abstract
251	Other Financial Liabilities	Concept (Text Block (HTML))	For Period		hmc:DisclosureOfOtherFinancialLiabilitiesExplanatory
252	1023 - Disclosure - Provisions	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfOtherProvisionsExplanatory
253	Implied Table	Table	*	*	implied:Table
254	Text block1 [abstract]	Abstract			hmc:TextBlock1Abstract
255	Provisions	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfOtherProvisionsExplanatory
256	1024 - Disclosure - Employee Benefits	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfEmployeeBenefitsExplanatory
257	Implied Table	Table	*	*	implied:Table
258	Text block1 [abstract]	Abstract			hmc:TextBlock1Abstract
259	Employee Benefits	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfEmployeeBenefitsExplanatory
260	1025 - Disclosure - Equity	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfShareCapitalReservesAndOtherEquityInterestExplanatory
261	Implied Table	Table	*	*	implied:Table
262	Text block1 [abstract]	Abstract			hmc:TextBlock1Abstract
263	Equity	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfShareCapitalReservesAndOtherEquityInterestExplanatory
264	1026 - Disclosure - Sales Revenue	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfRevenueExplanatory
265	Implied Table	Table	*	*	implied:Table
266	Text block1 [abstract]	Abstract			hmc:TextBlock1Abstract
267	Sales Revenue	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfRevenueExplanatory
268	1027 - Disclosure - Research and Development	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfResearchAndDevelopmentExpenseExplanatory
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270	Text block1 [abstract]	Abstract			hmc:TextBlock1Abstract
271	Research and Development	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfResearchAndDevelopmentExpenseExplanatory
272	1028 - Disclosure - Finance Income and Finance Costs	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfFinanceIncomeExpenseExplanatory
273	Implied Table	Table	*	*	implied:Table
274	Text block1 [abstract]	Abstract			hmc:TextBlock1Abstract
275	Finance Income and Finance Costs	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfFinanceIncomeExpenseExplanatory
276	1029 - Disclosure - Income Taxes	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfIncomeTaxExplanatory
277	Implied Table	Table	*	*	implied:Table
278	Text block1 [abstract]	Abstract			hmc:TextBlock1Abstract
279	Income Taxes	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfIncomeTaxExplanatory
280	1030 - Disclosure - Earnings Per Share	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfEarningsPerShareExplanatory
281	Implied Table	Table	*	*	implied:Table
282	Text block1 [abstract]	Abstract			hmc:TextBlock1Abstract
283	Earnings Per Share	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfEarningsPerShareExplanatory
284	1031 - Disclosure - Financial Risk Management	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfFinancialRiskManagementExplanatory
285	Implied Table	Table	*	*	implied:Table
286	Text block1 [abstract]	Abstract			hmc:TextBlock1Abstract
287	Financial Risk Management	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfFinancialRiskManagementExplanatory
288	1032 - Disclosure - Fair Value	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfFairValueMeasurementExplanatory
289	Implied Table	Table	*	*	implied:Table
290	Text block1 [abstract]	Abstract			hmc:TextBlock1Abstract
291	Fair Value	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfFairValueMeasurementExplanatory
292	1033 - Disclosure - Offsetting of Financial Assets and Financial Liabilities	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfOffsettingOfFinancialAssetsAndFinancialLiabilitiesExplanatory
293	Implied Table	Table	*	*	implied:Table
294	Text block1 [abstract]	Abstract			hmc:TextBlock1Abstract
295	Offsetting of Financial Assets and Financial Liabilities	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfOffsettingOfFinancialAssetsAndFinancialLiabilitiesExplanatory
296	1034 - Disclosure - Commitments and Contingent Liabilities	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfCommitmentsAndContingentLiabilitiesExplanatory
297	Implied Table	Table	*	*	implied:Table
298	Text block1 [abstract]	Abstract			hmc:TextBlock1Abstract
299	Commitments and Contingent Liabilities	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfCommitmentsAndContingentLiabilitiesExplanatory
300	1035 - Disclosure - Structured Entities	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfInformationAboutConsolidatedStructuredEntitiesExplanatory
301	Implied Table	Table	*	*	implied:Table
302	Text block1 [abstract]	Abstract			hmc:TextBlock1Abstract
303	Structured Entities	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfInformationAboutConsolidatedStructuredEntitiesExplanatory
304	1036 - Disclosure - Related Parties	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfRelatedPartyExplanatory
305	Implied Table	Table	*	*	implied:Table
306	Text block1 [abstract]	Abstract			hmc:TextBlock1Abstract
307	Related Parties	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfRelatedPartyExplanatory
308	1037 - Disclosure - Subsequent Event	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfEventsAfterReportingPeriodExplanatory
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311	Subsequent Event	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfEventsAfterReportingPeriodExplanatory
312	1038 - Disclosure - Approval of Release of Consolidated Financial Statements	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfAuthorisationOfFinancialStatementsExplanatory
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314	Text block1 [abstract]	Abstract			hmc:TextBlock1Abstract
315	Approval of Release of Consolidated Financial Statements	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfAuthorisationOfFinancialStatementsExplanatory
316	1039 - Disclosure - Significant Accounting Policies (Policies)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfSummaryOfSignificantAccountingPoliciesExplanatoryPolicies
317	Statement [Table]	Table	*	*	us-gaap:StatementTable
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319	Property, plant and equipment by operating lease status [member]	Member			ifrs-full:PropertyPlantAndEquipmentByOperatingLeaseStatusMember
320	Equipment on operating leases [member]	Member			ifrs-full:PropertyPlantAndEquipmentSubjectToOperatingLeasesMember
321	Property, plant and equipment [member]	Member			ifrs-full:PropertyPlantAndEquipmentNotSubjectToOperatingLeasesMember
322	Statement [Line Items]	LineItems			us-gaap:StatementLineItems
323	Basis of Consolidation	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfBasisOfConsolidationExplanatory
324	Investments in Affiliates and Joint Ventures (Investments Accounted for Using the Equity Method)	Concept (Text Block (HTML))	For Period		ifrs-full:DescriptionOfAccountingPolicyForInvestmentInAssociatesAndJointVenturesExplanatory
325	Foreign Currency Translations	Concept (Text Block (HTML))	For Period		ifrs-full:DescriptionOfAccountingPolicyForForeignCurrencyTranslationExplanatory
326	Financial Instruments	Concept (Text Block (HTML))	For Period		ifrs-full:DescriptionOfAccountingPolicyForFinancialInstrumentsExplanatory
327	Inventories	Concept (Text Block (HTML))	For Period		ifrs-full:DescriptionOfAccountingPolicyForMeasuringInventories
328	Property, Plant and Equipment	Concept (Text Block (HTML))	For Period		ifrs-full:DescriptionOfAccountingPolicyForPropertyPlantAndEquipmentExplanatory
329	Intangible Assets	Concept (Text Block (HTML))	For Period		ifrs-full:DescriptionOfAccountingPolicyForIntangibleAssetsAndGoodwillExplanatory
330	Lease	Concept (Text Block (HTML))	For Period		ifrs-full:DescriptionOfAccountingPolicyForLeasesExplanatory
331	Impairment	Concept (Text Block (HTML))	For Period		ifrs-full:DescriptionOfAccountingPolicyForImpairmentOfAssetsExplanatory
332	Provisions	Concept (Text Block (HTML))	For Period		ifrs-full:DescriptionOfAccountingPolicyForProvisionsExplanatory
333	Employee Benefits	Concept (Text Block (HTML))	For Period		ifrs-full:DescriptionOfAccountingPolicyForEmployeeBenefitsExplanatory
334	Equity	Concept (Text Block (HTML))	For Period		ifrs-full:DescriptionOfAccountingPolicyForIssuedCapitalExplanatory
335	Revenue Recognition	Concept (Text Block (HTML))	For Period		ifrs-full:DescriptionOfAccountingPolicyForRecognitionOfRevenue
336	Income Taxes	Concept (Text Block (HTML))	For Period		ifrs-full:DescriptionOfAccountingPolicyForIncomeTaxExplanatory
337	Earnings per Share	Concept (Text Block (HTML))	For Period		ifrs-full:DescriptionOfAccountingPolicyForEarningsPerShareExplanatory
338	1040 - Disclosure - Segment Information (Tables)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfEntitysReportableSegmentsExplanatoryTables
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340	Text block1 [abstract]	Abstract			hmc:TextBlock1Abstract
341	Summary of Segment Information	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfOperatingSegmentsExplanatory
342	Sales Revenue by Product or Service Groups	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfProductsAndServicesExplanatory
343	Sales Revenue and Carrying Amounts of Non-current Assets Other Than Financial Instruments and Deferred Tax Assets Based on Location	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfGeographicalAreasExplanatory
344	Supplemental Geographical Information Based on Location	Concept (Text Block (HTML))	For Period		hmc:DisclosureOfSupplementalGeographicalInformationExplanatory
345	1041 - Disclosure - Cash and Cash Equivalents (Tables)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfCashAndCashEquivalentsExplanatoryTables
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348	Summary of Cash and Cash Equivalents	Concept (Text Block (HTML))	For Period		hmc:DisclosureOfDetailedInformationAboutCashAndCashEquivalentsExplanatory
349	1042 - Disclosure - Trade Receivables (Tables)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfTradeAndOtherReceivablesExplanatoryTables
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353	Trade receivables [member]	Member			ifrs-full:TradeReceivablesMember
354	Statement [Line Items]	LineItems			us-gaap:StatementLineItems
355	Summary of Financial Assets	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfFinancialAssetsExplanatory
356	1043 - Disclosure - Receivables from Financial Services (Tables)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfLoansAndAdvancesToCustomersExplanatoryTables
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359	Financial instruments, class [member]	Member			ifrs-full:ClassesOfFinancialInstrumentsMember
360	Trade receivables [member]	Member			ifrs-full:TradeReceivablesMember
361	Other financial assets [member]	Member			hmc:OtherFinancialAssetMember
362	Receivables from financial services [Member]	Member			hmc:ReceivablesFromFinancialServicesMember
363	Statement [Line Items]	LineItems			us-gaap:StatementLineItems
364	Changes in Allowance for Doubtful Accounts	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfAllowanceForCreditLossesExplanatory
365	Summary of Receivables from Financial Services	Concept (Text Block (HTML))	For Period		hmc:DisclosureOfDetailedInformationOfLoansAndAdvancesToCustomersExplanatory
366	Gross Investment in Lease and Present Value of Minimum Lease Payments Receivable	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfFinanceLeaseAndOperatingLeaseByLessorExplanatory
367	1044 - Disclosure - Other Financial Assets (Tables)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfOtherFinancialAssetsExplanatoryTables
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369	Text block1 [abstract]	Abstract			hmc:TextBlock1Abstract
370	Summary of Other Financial Assets	Concept (Text Block (HTML))	For Period		hmc:DisclosureOfOtherFinancialAssetsByComponentExplanatory
371	Major Securities Included in Financial Assets Measured at Fair Value Through Other Comprehensive Income	Concept (Text Block (HTML))	For Period		hmc:DisclosureOfFinancialAssetsAtFairValueThroughOtherComprehensiveIncomeExplanatory
372	1045 - Disclosure - Inventories (Tables)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfInventoriesExplanatoryTables
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375	Summary of Inventories	Concept (Text Block (HTML))	For Period		hmc:DisclosureOfDetailedInformationAboutInventoriesExplanatory
376	1046 - Disclosure - Investments Accounted for Using the Equity Method (Tables)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfInvestmentsAccountedForUsingEquityMethodExplanatoryTables
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378	Text block1 [abstract]	Abstract			hmc:TextBlock1Abstract
379	Equity in Affiliates and Joint Ventures	Concept (Text Block (HTML))	For Period		hmc:DisclosureOfDetailedInformationAboutInvestmentsAccountedForUsingEquityMethodExplanatory
380	Share of Comprehensive Income of Affiliates and Joint Ventures	Concept (Text Block (HTML))	For Period		hmc:DisclosureOfComprehensiveIncomeOfAffiliatesAndJointVenturesExplanatory
381	Combined Financial Information of Affiliates and Joint Ventures	Concept (Text Block (HTML))	For Period		hmc:DisclosureOfCombinedFinancialInformationOfAffiliatesAndJointVenturesExplanatory
382	1047 - Disclosure - Property, Plant and Equipment (Tables)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfPropertyPlantAndEquipmentExplanatoryTables
383	Statement [Table]	Table	*	*	us-gaap:StatementTable
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385	Property, plant and equipment by operating lease status [member]	Member			ifrs-full:PropertyPlantAndEquipmentByOperatingLeaseStatusMember
386	Equipment on operating leases [member]	Member			ifrs-full:PropertyPlantAndEquipmentSubjectToOperatingLeasesMember
387	Property, plant and equipment [member]	Member			ifrs-full:PropertyPlantAndEquipmentNotSubjectToOperatingLeasesMember
388	Statement [Line Items]	LineItems			us-gaap:StatementLineItems
389	Summary of Property, Plant and Equipment	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfDetailedInformationAboutPropertyPlantAndEquipmentExplanatory
390	Future Minimum Lease Payments Expected to be Received under Non-cancellable Operating Leases to be Received	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfMaturityAnalysisOfOperatingLeasePaymentsExplanatory
391	1048 - Disclosure - Intangible Assets (Tables)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfIntangibleAssetsExplanatoryTables
392	Implied Table	Table	*	*	implied:Table
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394	Changes in Cost, Accumulated Amortization and Impairment Losses, and Carrying Amounts of Intangible Assets	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfDetailedInformationAboutIntangibleAssetsExplanatory
395	1049 - Disclosure - Trade Payables (Tables)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfTradeAndOtherPayablesExplanatoryTables
396	Implied Table	Table	*	*	implied:Table
397	Text block1 [abstract]	Abstract			hmc:TextBlock1Abstract
398	Summary of Trade Payables	Concept (Text Block (HTML))	For Period		hmc:DisclosureOfDetailedInformationAboutTradeAndOtherPayablesExplanatory
399	1050 - Disclosure - Financing Liabilities (Tables)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfBorrowingsExplanatoryTables
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402	Financial instruments, class [member]	Member			ifrs-full:ClassesOfFinancialInstrumentsMember
403	Current borrowings [member]	Member			hmc:CurrentBorrowingsMember
404	Non-current liabilities [member]	Member			hmc:NoncurrentBorrowingsMember
405	Statement [Line Items]	LineItems			us-gaap:StatementLineItems
406	Summary of Financing Liabilities	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsExplanatory
407	Interest Rates for Financing Liabilities	Concept (Text Block (HTML))	For Period		hmc:DisclosureOfInterestRatesForFinancingLiabilitiesExplanatory
408	Pledged Assets for Financing Liabilities	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfCollateralExplanatory
409	The Changes in Liabilities Arising from Financing Activities	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfReconciliationOfLiabilitiesArisingFromFinancingActivitiesExplanatory
410	1051 - Disclosure - Other Financial Liabilities (Tables)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfOtherFinancialLiabilitiesExplanatoryTables
411	Implied Table	Table	*	*	implied:Table
412	Text block1 [abstract]	Abstract			hmc:TextBlock1Abstract
413	Summary of Other Financial Liabilities	Concept (Text Block (HTML))	For Period		hmc:DisclosureOfDetailedInformationAboutOtherFinancialLiabilitiesExplanatory
414	1052 - Disclosure - Provisions (Tables)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfOtherProvisionsExplanatoryTables
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418	Current Liabilities and Non-current Liabilities of Provisions	Concept (Text Block (HTML))	For Period		hmc:DisclosureOfCurrentLiabilitiesAndNoncurrentLiabilitiesOfProvisionsExplanatory
419	1053 - Disclosure - Employee Benefits (Tables)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfEmployeeBenefitsExplanatoryTables
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422	Changes in Present Value of Defined Benefit Obligations and Fair Value of Plan Assets	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfNetDefinedBenefitLiabilityAssetExplanatory
423	Fair Value of Japanese and Foreign Pension Plan Assets By Asset Category	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfFairValueOfPlanAssetsExplanatory
424	Significant Actuarial Assumptions Used to Determine Present Value of Defined Benefit Obligations	Concept (Text Block (HTML))	For Period		hmc:DisclosureOfActuarialAssumptionsToDeterminePresentValueOfDefinedBenefitObligationsExplanatory
425	Effects on Defined Benefit Obligations Due to Increase or Decrease in Discount Rate	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfSensitivityAnalysisForActuarialAssumptionsExplanatory
426	Weighted Average Duration of Defined Benefit Obligations	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfInformationAboutMaturityProfileOfDefinedBenefitObligationExplanatory
427	Personnel Expenses Included in Consolidated Statements of Income	Concept (Text Block (HTML))	For Period		hmc:DisclosureOfPersonnelExpensesExplanatory
428	1054 - Disclosure - Equity (Tables)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfShareCapitalReservesAndOtherEquityInterestExplanatoryTables
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430	Text block1 [abstract]	Abstract			hmc:TextBlock1Abstract
431	Financial Liabilities and Equity	Concept (Text Block (HTML))	For Period		hmc:DisclosureOfFinancialLiabilitiesAndEquityExplanatory
432	Total Number of Shares Authorized and Issued	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfIssuedCapitalExplanatory
433	Total Number of Treasury Stock Held	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfTreasurySharesExplanatory
434	Changes in Other Components of Equity	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfReservesAndOtherEquityInterestExplanatory
435	Each Component of Other Comprehensive Income and Related Tax Effect Including Non-controlling Interests	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfAnalysisOfOtherComprehensiveIncomeByItemExplanatory
436	Components of Other Comprehensive Income Included in Non-controlling Interests	Concept (Text Block (HTML))	For Period		hmc:DisclosureOfComponentsOfOtherComprehensiveIncomeLossIncludedInNoncontrollingInterestExplanatory
437	Dividends from Retained Earnings	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfDividendsExplanatory
438	1055 - Disclosure - Sales Revenue (Tables)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfRevenueExplanatoryTables
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441	Summary of Sales Revenue	Concept (Text Block (HTML))	For Period		hmc:DisclosureOfDetailedInformationAboutRevenueExplanatory
442	1056 - Disclosure - Research and Development (Tables)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfResearchAndDevelopmentExpenseExplanatoryTables
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445	Summary of Research and Development Costs	Concept (Text Block (HTML))	For Period		hmc:DisclosureOfDetailedInformationOfResearchAndDevelopmentExpenseExplanatory
446	1057 - Disclosure - Finance Income and Finance Costs (Tables)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/NotesToFinancialStatementsDisclosureOfFinanceIncomeExpenseExplanatoryTables
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453	Profit Before Income Taxes and Income Tax Expense	Concept (Text Block (HTML))	For Period		hmc:DisclosureOfDetailedInformationAboutIncomeTaxExpenseExplanatory
454	Reconciliation of Statutory Income Tax Rate to Average Effective Tax Rate	Concept (Text Block (HTML))	For Period		hmc:DisclosureOfReconciliationOfStatutoryIncomeTaxRateToAverageEffectiveTaxRateExplanatory
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478	Non-derivative Financial Liabilities by Maturity	Concept (Text Block (HTML))	For Period		ifrs-full:MaturityAnalysisForNonderivativeFinancialLiabilities
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538	Disclosure of operating segments [table]	Table	*	*	ifrs-full:DisclosureOfOperatingSegmentsTable
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600	1072 - Disclosure - Segment Information - Supplemental Geographical Information Based on Location (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureSegmentInformationSupplementalGeographicalInformationBasedOnLocation
601	Disclosure of geographical areas [table]	Table	*	*	ifrs-full:DisclosureOfGeographicalAreasTable
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628	Disclosure of geographical areas [line items]	LineItems			ifrs-full:DisclosureOfGeographicalAreasLineItems
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636	1075 - Disclosure - Trade Receivables - Summary of Trade Receivables (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureTradeReceivablesSummaryOfTradeReceivables
637	Disclosure of financial assets [table]	Table	*	*	ifrs-full:DisclosureOfFinancialAssetsTable
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658	Balance at end of year	Concept (Monetary)	As Of	Credit	ifrs-full:AllowanceAccountForCreditLossesOfFinancialAssets
659	1077 - Disclosure - Receivables from Financial Services - Summary of Receivables from Financial Services (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureReceivablesFromFinancialServicesSummaryOfReceivablesFromFinancialServices
660	Disclosure of financial assets [table]	Table	*	*	ifrs-full:DisclosureOfFinancialAssetsTable
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695	Wholesale [member]	Member			ifrs-full:CorporateLoansMember
696	Financial Services receivables [Member]	Member			hmc:FinancialServicesReceivablesMember
697	Disclosure of financial assets [line items]	LineItems			ifrs-full:DisclosureOfFinancialAssetsLineItems
698	Balance at beginning of year	Concept (Monetary)	As Of	Credit	ifrs-full:AllowanceAccountForCreditLossesOfFinancialAssets
699	Provision	Concept (Monetary)	For Period		ifrs-full:AdditionalAllowanceRecognisedInProfitOrLossAllowanceAccountForCreditLossesOfFinancialAssets
700	Charge-offs	Concept (Monetary)	For Period	Debit	ifrs-full:UtilisationAllowanceAccountForCreditLossesOfFinancialAssets
701	Recoveries	Concept (Monetary)	For Period	Credit	hmc:IncreaseThroughRecoveriesAllowanceAccountForCreditLossesOfFinancialAssets
702	Exchange differences on translating foreign operations	Concept (Monetary)	For Period	Credit	ifrs-full:IncreaseDecreaseThroughNetExchangeDifferencesAllowanceAccountForCreditLossesOfFinancialAssets
703	Balance at end of year	Concept (Monetary)	As Of	Credit	ifrs-full:AllowanceAccountForCreditLossesOfFinancialAssets
704	1080 - Disclosure - Other Financial Assets - Summary of Other Financial Assets (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureOtherFinancialAssetsSummaryOfOtherFinancialAssets
705	Disclosure of financial assets [table]	Table	*	*	ifrs-full:DisclosureOfFinancialAssetsTable
706	Categories of financial assets [axis]	Axis			ifrs-full:CategoriesOfFinancialAssetsAxis
707	Financial assets, category [member]	Member			ifrs-full:FinancialAssetsCategoryMember
708	Financial assets measured at amortized cost [member]	Member			ifrs-full:FinancialAssetsAtAmortisedCostCategoryMember
709	Financial assets measured at fair value through other comprehensive income [member]	Member			ifrs-full:FinancialAssetsMeasuredAtFairValueThroughOtherComprehensiveIncomeCategoryMember
710	Financial assets measured at fair value through profit or loss [member]	Member			ifrs-full:FinancialAssetsAtFairValueThroughProfitOrLossCategoryMember
711	Classes of financial assets [axis]	Axis			ifrs-full:ClassesOfFinancialAssetsAxis
712	Financial assets, class [member]	Member			ifrs-full:FinancialAssetsMember
713	Receivables other than trade receivables and receivables from financial services [member]	Member			hmc:OtherReceivablesMember
714	Derivatives [member]	Member			ifrs-full:DerivativesMember
715	Debt securities [member]	Member			ifrs-full:DebtSecuritiesMember
716	Guaranty deposits [member]	Member			hmc:GuarantyDepositsMember
717	Restricted cash [member]	Member			hmc:RestrictedCashMember
718	Equity securities [member]	Member			ifrs-full:EquityInvestmentsMember
719	Other financial assets [member]	Member			hmc:OtherFinancialAssetMember
720	Allowance for doubtful accounts [member]	Member			ifrs-full:AllowanceForCreditLossesMember
721	Disclosure of financial assets [line items]	LineItems			ifrs-full:DisclosureOfFinancialAssetsLineItems
722	Other financial assets	Concept (Monetary)	As Of	Debit	ifrs-full:OtherFinancialAssets
723	Current assets	Concept (Monetary)	As Of	Debit	ifrs-full:OtherCurrentFinancialAssets
724	Non-current assets	Concept (Monetary)	As Of	Debit	ifrs-full:OtherNoncurrentFinancialAssets
725	1081 - Disclosure - Other Financial Assets - Changes in the Allowance for Doubtful Accounts (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureOtherFinancialAssetsChangesInTheAllowanceForDoubtfulAccounts
726	Disclosure of Doubtful Accounts for Other Financial Assets1 [Table]	Table	*	*	hmc:DisclosureOfDoubtfulAccountsForOtherFinancialAssets1Table
727	Classes of financial assets [axis]	Axis			ifrs-full:ClassesOfFinancialAssetsAxis
728	Financial assets, class [member]	Member			ifrs-full:FinancialAssetsMember
729	Other financial assets [member]	Member			hmc:OtherFinancialAssetMember
730	Disclosure of Doubtful Accounts for Other Financial Assets [Line Items]	LineItems			hmc:DisclosureOfDoubtfulAccountsForOtherFinancialAssetsLineItems
731	Balance at beginning of year	Concept (Monetary)	As Of	Credit	ifrs-full:AllowanceAccountForCreditLossesOfFinancialAssets
732	Provision	Concept (Monetary)	For Period		ifrs-full:AdditionalAllowanceRecognisedInProfitOrLossAllowanceAccountForCreditLossesOfFinancialAssets
733	Charge-offs	Concept (Monetary)	For Period	Debit	ifrs-full:UtilisationAllowanceAccountForCreditLossesOfFinancialAssets
734	Exchange differences on translating foreign operations	Concept (Monetary)	For Period	Credit	ifrs-full:IncreaseDecreaseThroughNetExchangeDifferencesAllowanceAccountForCreditLossesOfFinancialAssets
735	Balance at end of year	Concept (Monetary)	As Of	Credit	ifrs-full:AllowanceAccountForCreditLossesOfFinancialAssets
736	1082 - Disclosure - Other Financial Assets - Major Securities Included in Financial Assets Measured at Fair Value Through Other Comprehensive Income (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureOtherFinancialAssetsMajorSecuritiesIncludedInFinancialAssetsMeasuredAtFairValueThroughOtherComprehensiveIncome
737	Disclosure of Doubtful Accounts for Other Financial Assets1 [Table]	Table	*	*	hmc:DisclosureOfDoubtfulAccountsForOtherFinancialAssets1Table
738	Legal Entity [Axis]	Axis			dei:LegalEntityAxis
739	Entity [Domain]	Member			dei:EntityDomain
740	Sirius XM Holdings Inc. [member]	Member			hmc:SiriusXMHoldingsIncMember
741	Stanley Electric Co., Ltd. [member]	Member			hmc:StanleyElectricCoLtdMember
742	Mitsubishi UFJ Financial Group, Inc. [member]	Member			hmc:MitsubishiUFJFinancialGroupIncMember
743	Shindengen Electric Manufacturing Co., Ltd. [member]	Member			hmc:ShindengenElectricManufacturingCoLtdMember
744	NIPPON SEIKI CO., LTD. [member]	Member			hmc:NIPPONSEIKICoLtdMember
745	Daido Steel Co., Ltd. [member]	Member			hmc:DaidoSteelCoLtdMember
746	Disclosure of Doubtful Accounts for Other Financial Assets [Line Items]	LineItems			hmc:DisclosureOfDoubtfulAccountsForOtherFinancialAssetsLineItems
747	Financial assets measured at fair value through other comprehensive income	Concept (Monetary)	As Of	Debit	ifrs-full:FinancialAssetsAtFairValueThroughOtherComprehensiveIncome
748	1083 - Disclosure - Inventories - Summary of Inventories (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureInventoriesSummaryOfInventories
749	Implied Table	Table	*	*	implied:Table
750	Classes of current inventories [abstract]	Abstract			ifrs-full:ClassesOfInventoriesAbstract
751	Finished goods	Concept (Monetary)	As Of	Debit	ifrs-full:FinishedGoods
752	Work in process	Concept (Monetary)	As Of	Debit	ifrs-full:WorkInProgress
753	Raw materials	Concept (Monetary)	As Of	Debit	ifrs-full:RawMaterials
754	Total	Concept (Monetary)	As Of	Debit	ifrs-full:Inventories
755	1084 - Disclosure - Inventories - Additional Information (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureInventoriesAdditionalInformation
756	Implied Table	Table	*	*	implied:Table
757	Classes of current inventories [abstract]	Abstract			ifrs-full:ClassesOfInventoriesAbstract
758	Write-down of inventories recognized as an expense	Concept (Monetary)	For Period		ifrs-full:InventoryWritedown2011
759	1085 - Disclosure - Investments Accounted for Using the Equity Method - Equity in Affiliates and Joint Ventures (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureInvestmentsAccountedForUsingTheEquityMethodEquityInAffiliatesAndJointVentures
760	Implied Table	Table	*	*	implied:Table
761	Disclosure of Investments Accounted for Using Equity Method [Abstract]	Abstract			hmc:DisclosureOfInvestmentsAccountedForUsingEquityMethodAbstract
762	Investments accounted for using the equity method, Affiliates	Concept (Monetary)	As Of	Debit	ifrs-full:InvestmentsInAssociatesAccountedForUsingEquityMethod
763	Investments accounted for using the equity method, Joint ventures	Concept (Monetary)	As Of	Debit	ifrs-full:InvestmentsInJointVenturesAccountedForUsingEquityMethod
764	Investments accounted for using the equity method, Total	Concept (Monetary)	As Of	Debit	ifrs-full:InvestmentAccountedForUsingEquityMethod
765	Honda's equity of undistributed earnings, Affiliates	Concept (Monetary)	As Of	Credit	hmc:ShareOfRetainedEarningOfAssociatesAccountedForUsingEquityMethod
766	Honda's equity of undistributed earnings, Joint ventures	Concept (Monetary)	As Of	Credit	hmc:ShareOfRetainedEarningOfJointVenturesAccountedForUsingEquityMethod
767	Honda's equity of undistributed earnings, Total	Concept (Monetary)	As Of	Credit	hmc:ShareOfRetainedEarningOfInvestmentsAccountedForUsingEquityMethod
768	1086 - Disclosure - Investments Accounted for Using the Equity Method - Additional Information (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureInvestmentsAccountedForUsingTheEquityMethodAdditionalInformation
769	Disclosure of investments accounted for using equity method [Table]	Table	*	*	hmc:DisclosureOfInvestmentsAccountedForUsingEquityMethodTable
770	Classes of assets [axis]	Axis			ifrs-full:ClassesOfAssetsAxis
771	Assets [member]	Member			ifrs-full:ClassesOfAssetsMember
772	Investments accounted for using equity method [member]	Member			ifrs-full:InvestmentsAccountedForUsingEquityMethodMember
773	Disclosure of investments accounted for using equity method [line items]	LineItems			hmc:DisclosureOfInvestmentsAccountedForUsingEquityMethodLineItems
774	Impairment losses recognized on certain investments accounted for using the equity method	Concept (Monetary)	For Period	Debit	ifrs-full:ImpairmentLoss
775	Reversal of impairment losses	Concept (Monetary)	For Period	Credit	ifrs-full:ReversalOfImpairmentLoss
776	1087 - Disclosure - Investments Accounted for Using the Equity Method - Share of Comprehensive Income of Affiliates and Joint Ventures (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureInvestmentsAccountedForUsingTheEquityMethodShareOfComprehensiveIncomeOfAffiliatesAndJointVentures
777	Disclosure of investments accounted for using equity method [Table]	Table	*	*	hmc:DisclosureOfInvestmentsAccountedForUsingEquityMethodTable
778	Classes of assets [axis]	Axis			ifrs-full:ClassesOfAssetsAxis
779	Assets [member]	Member			ifrs-full:ClassesOfAssetsMember
780	Affiliates [member]	Member			ifrs-full:AssociatesMember
781	Joint ventures [member]	Member			ifrs-full:JointVenturesMember
782	Disclosure of investments accounted for using equity method [line items]	LineItems			hmc:DisclosureOfInvestmentsAccountedForUsingEquityMethodLineItems
783	Profit for the year	Concept (Monetary)	For Period	Credit	ifrs-full:ShareOfProfitLossOfAssociatesAndJointVenturesAccountedForUsingEquityMethod
784	Other comprehensive income	Concept (Monetary)	For Period	Credit	ifrs-full:ShareOfOtherComprehensiveIncomeOfAssociatesAndJointVenturesAccountedForUsingEquityMethod
785	Comprehensive income for the year	Concept (Monetary)	For Period	Credit	ifrs-full:ShareOfTotalComprehensiveIncomeOfAssociatesAndJointVenturesAccountedForUsingEquityMethod
786	1088 - Disclosure - Investments Accounted for Using the Equity Method - Combined Financial Information of Affiliates and Joint Ventures (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureInvestmentsAccountedForUsingTheEquityMethodCombinedFinancialInformationOfAffiliatesAndJointVentures
787	Disclosure of investments accounted for using equity method [Table]	Table	*	*	hmc:DisclosureOfInvestmentsAccountedForUsingEquityMethodTable
788	Classes of assets [axis]	Axis			ifrs-full:ClassesOfAssetsAxis
789	Assets [member]	Member			ifrs-full:ClassesOfAssetsMember
790	Affiliates [member]	Member			ifrs-full:AssociatesMember
791	Joint ventures [member]	Member			ifrs-full:JointVenturesMember
792	Segments [axis]	Axis			ifrs-full:SegmentsAxis
793	Segments [member]	Member			ifrs-full:SegmentsMember
794	Motorcycle business [member]	Member			hmc:MotorcycleBusinessMember
795	Automobile business [member]	Member			hmc:AutomobileBusinessMember
796	Power product and other businesses [member]	Member			hmc:PowerProductAndOtherBusinessesMember
797	Disclosure of investments accounted for using equity method [line items]	LineItems			hmc:DisclosureOfInvestmentsAccountedForUsingEquityMethodLineItems
798	Current assets	Concept (Monetary)	As Of	Debit	ifrs-full:CurrentAssets
799	Non-current assets	Concept (Monetary)	As Of	Debit	ifrs-full:NoncurrentAssets
800	Total assets	Concept (Monetary)	As Of	Debit	ifrs-full:Assets
801	Current liabilities	Concept (Monetary)	As Of	Credit	ifrs-full:CurrentLiabilities
802	Non-current liabilities	Concept (Monetary)	As Of	Credit	ifrs-full:NoncurrentLiabilities
803	Total liabilities	Concept (Monetary)	As Of	Credit	ifrs-full:Liabilities
804	Total equity	Concept (Monetary)	As Of	Credit	ifrs-full:Equity
805	Sales revenue	Concept (Monetary)	For Period	Credit	ifrs-full:Revenue
806	Profit for the year	Concept (Monetary)	For Period	Credit	ifrs-full:ProfitLoss
807	1089 - Disclosure - Equipment on Operating Leases - Changes in Cost, Accumulated Depreciation and Impairment Losses, and the Carrying Amounts of Equipment on Operating Leases (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureEquipmentOnOperatingLeasesChangesInCostAccumulatedDepreciationAndImpairmentLossesAndTheCarryingAmountsOfEquipmentOnOperatingLeases
808	Disclosure of detailed information about property, plant and equipment [table]	Table	*	*	ifrs-full:DisclosureOfPropertyPlantAndEquipmentTable
809	Property, plant and equipment by operating lease status [axis]	Axis			ifrs-full:PropertyPlantAndEquipmentByOperatingLeaseStatusAxis
810	Property, plant and equipment by operating lease status [member]	Member			ifrs-full:PropertyPlantAndEquipmentByOperatingLeaseStatusMember
811	Equipment on operating leases [member]	Member			ifrs-full:PropertyPlantAndEquipmentSubjectToOperatingLeasesMember
812	Carrying amount, accumulated depreciation, amortisation and impairment and gross carrying amount [axis]	Axis			ifrs-full:CarryingAmountAccumulatedDepreciationAmortisationAndImpairmentAndGrossCarryingAmountAxis
813	Carrying amount [member]	Member			ifrs-full:CarryingAmountMember
814	Gross carrying amount [member]	Member			ifrs-full:GrossCarryingAmountMember
815	Accumulated depreciation, amortization and impairment losses [member]	Member			ifrs-full:AccumulatedDepreciationAmortisationAndImpairmentMember
816	Disclosure of detailed information about property, plant and equipment [line items]	LineItems			ifrs-full:DisclosureOfPropertyPlantAndEquipmentLineItems
817	Beginning balance	Concept (Monetary)	As Of	Debit	ifrs-full:PropertyPlantAndEquipment
818	Additions	Concept (Monetary)	For Period	Debit	ifrs-full:AdditionsOtherThanThroughBusinessCombinationsPropertyPlantAndEquipment
819	Depreciation	Concept (Monetary)	For Period		ifrs-full:DepreciationPropertyPlantAndEquipment
820	Sales or disposal	Concept (Monetary)	For Period	Credit	ifrs-full:DisposalsPropertyPlantAndEquipment
821	Exchange differences on translating foreign operations	Concept (Monetary)	For Period	Debit	ifrs-full:IncreaseDecreaseThroughNetExchangeDifferencesPropertyPlantAndEquipment
822	Other	Concept (Monetary)	For Period	Debit	ifrs-full:IncreaseDecreaseThroughOtherChangesPropertyPlantAndEquipment
823	Ending balance	Concept (Monetary)	As Of	Debit	ifrs-full:PropertyPlantAndEquipment
824	1090 - Disclosure - Equipment on Operating Leases - Future Minimum Lease Payments Expected to be Received under Non-cancellable Operating Leases to be Received (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureEquipmentOnOperatingLeasesFutureMinimumLeasePaymentsExpectedToBeReceivedUnderNoncancellableOperatingLeasesToBeReceived
825	Disclosure of finance lease and operating lease by lessor [table]	Table	*	*	ifrs-full:DisclosureOfFinanceLeaseAndOperatingLeaseByLessorTable
826	Property, plant and equipment by operating lease status [axis]	Axis			ifrs-full:PropertyPlantAndEquipmentByOperatingLeaseStatusAxis
827	Property, plant and equipment by operating lease status [member]	Member			ifrs-full:PropertyPlantAndEquipmentByOperatingLeaseStatusMember
828	Equipment on operating leases [member]	Member			ifrs-full:PropertyPlantAndEquipmentSubjectToOperatingLeasesMember
829	Maturity [axis]	Axis			ifrs-full:MaturityAxis
830	Aggregated time bands [member]	Member			ifrs-full:AggregatedTimeBandsMember
831	Within 1 year [member]	Member			ifrs-full:NotLaterThanOneYearMember
832	Between 1 and 5 years [member]	Member			ifrs-full:LaterThanOneYearAndNotLaterThanFiveYearsMember
833	Disclosure of finance lease and operating lease by lessor [line items]	LineItems			ifrs-full:DisclosureOfFinanceLeaseAndOperatingLeaseByLessorLineItems
834	Future minimum lease payments expected to be received under non-cancelable operating leases	Concept (Monetary)	As Of	Debit	ifrs-full:MinimumLeasePaymentsReceivableUnderNoncancellableOperatingLease
835	1091 - Disclosure - Property Plant and Equipment - Changes in Cost, Accumulated Depreciation and Impairment Losses, and the Carrying Amounts of Property, Plant and Equipment (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosurePropertyPlantAndEquipmentChangesInCostAccumulatedDepreciationAndImpairmentLossesAndTheCarryingAmountsOfPropertyPlantAndEquipment
836	Disclosure of detailed information about property, plant and equipment [table]	Table	*	*	ifrs-full:DisclosureOfPropertyPlantAndEquipmentTable
837	Property, plant and equipment by operating lease status [axis]	Axis			ifrs-full:PropertyPlantAndEquipmentByOperatingLeaseStatusAxis
838	Property, plant and equipment by operating lease status [member]	Member			ifrs-full:PropertyPlantAndEquipmentByOperatingLeaseStatusMember
839	Property, plant and equipment [member]	Member			ifrs-full:PropertyPlantAndEquipmentNotSubjectToOperatingLeasesMember
840	Classes of property, plant and equipment [axis]	Axis			ifrs-full:ClassesOfPropertyPlantAndEquipmentAxis
841	Property, plant and equipment [member]	Member			ifrs-full:PropertyPlantAndEquipmentMember
842	Land [member]	Member			ifrs-full:LandMember
843	Buildings and structures [member]	Member			ifrs-full:BuildingsMember
844	Machinery and equipment [member]	Member			ifrs-full:MachineryMember
845	Construction in progress [member]	Member			ifrs-full:ConstructionInProgressMember
846	Carrying amount, accumulated depreciation, amortisation and impairment and gross carrying amount [axis]	Axis			ifrs-full:CarryingAmountAccumulatedDepreciationAmortisationAndImpairmentAndGrossCarryingAmountAxis
847	Carrying amount [member]	Member			ifrs-full:CarryingAmountMember
848	Gross carrying amount [member]	Member			ifrs-full:GrossCarryingAmountMember
849	Accumulated depreciation, amortization and impairment losses [member]	Member			ifrs-full:AccumulatedDepreciationAmortisationAndImpairmentMember
850	Disclosure of detailed information about property, plant and equipment [line items]	LineItems			ifrs-full:DisclosureOfPropertyPlantAndEquipmentLineItems
851	Beginning balance	Concept (Monetary)	As Of	Debit	ifrs-full:PropertyPlantAndEquipment
852	Additions	Concept (Monetary)	For Period	Debit	ifrs-full:AdditionsOtherThanThroughBusinessCombinationsPropertyPlantAndEquipment
853	Depreciation	Concept (Monetary)	For Period		ifrs-full:DepreciationPropertyPlantAndEquipment
854	Reclassification	Concept (Monetary)	For Period	Debit	ifrs-full:IncreaseDecreaseThroughTransfersPropertyPlantAndEquipment
855	Sales or disposal	Concept (Monetary)	For Period	Credit	ifrs-full:DisposalsPropertyPlantAndEquipment
856	Exchange differences on translating foreign operations	Concept (Monetary)	For Period	Debit	ifrs-full:IncreaseDecreaseThroughNetExchangeDifferencesPropertyPlantAndEquipment
857	Other	Concept (Monetary)	For Period	Debit	ifrs-full:IncreaseDecreaseThroughOtherChangesPropertyPlantAndEquipment
858	Ending balance	Concept (Monetary)	As Of	Debit	ifrs-full:PropertyPlantAndEquipment
859	1092 - Disclosure - Intangible Assets - Changes in Cost, Accumulated Amortization and Impairment Losses, and Carrying Amounts of Intangible Assets (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureIntangibleAssetsChangesInCostAccumulatedAmortizationAndImpairmentLossesAndCarryingAmountsOfIntangibleAssets
860	Disclosure of reconciliation of changes in intangible assets and goodwill [table]	Table	*	*	ifrs-full:DisclosureOfReconciliationOfChangesInIntangibleAssetsAndGoodwillTable
861	Classes of intangible assets and goodwill [axis]	Axis			ifrs-full:ClassesOfIntangibleAssetsAndGoodwillAxis
862	Intangible assets and goodwill [member]	Member			ifrs-full:IntangibleAssetsAndGoodwillMember
863	Capitalized development costs [member]	Member			ifrs-full:CapitalisedDevelopmentExpenditureMember
864	Software [member]	Member			ifrs-full:ComputerSoftwareMember
865	Other [member]	Member			ifrs-full:OtherIntangibleAssetsMember
866	Carrying amount, accumulated depreciation, amortisation and impairment and gross carrying amount [axis]	Axis			ifrs-full:CarryingAmountAccumulatedDepreciationAmortisationAndImpairmentAndGrossCarryingAmountAxis
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868	Gross carrying amount [member]	Member			ifrs-full:GrossCarryingAmountMember
869	Accumulated depreciation, amortization and impairment losses [member]	Member			ifrs-full:AccumulatedDepreciationAmortisationAndImpairmentMember
870	Disclosure of reconciliation of changes in intangible assets and goodwill [line items]	LineItems			ifrs-full:DisclosureOfReconciliationOfChangesInIntangibleAssetsAndGoodwillLineItems
871	Beginning balance	Concept (Monetary)	As Of	Debit	ifrs-full:IntangibleAssetsAndGoodwill
872	Additions	Concept (Monetary)	For Period	Debit	hmc:AdditionsToIntangibleAssetsWithGoodwill
873	Amortization	Concept (Monetary)	For Period		ifrs-full:AmortisationIntangibleAssetsOtherThanGoodwill
874	Internally developed	Concept (Monetary)	For Period	Debit	hmc:AdditionsThroughInternallyDevelopedIntangibleAssetsAndGoodwill
875	Sales or disposal	Concept (Monetary)	For Period	Credit	ifrs-full:DisposalsIntangibleAssetsAndGoodwill
876	Exchange differences on translating foreign operations	Concept (Monetary)	For Period	Debit	ifrs-full:IncreaseDecreaseThroughNetExchangeDifferencesIntangibleAssetsAndGoodwill
877	Other	Concept (Monetary)	For Period	Debit	ifrs-full:IncreaseDecreaseThroughOtherChangesIntangibleAssetsAndGoodwill
878	Ending balance	Concept (Monetary)	As Of	Debit	ifrs-full:IntangibleAssetsAndGoodwill
879	1093 - Disclosure - Trade Payables - Summary of Trade Payables (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureTradePayablesSummaryOfTradePayables
880	Disclosure of financial liabilities [table]	Table	*	*	ifrs-full:DisclosureOfFinancialLiabilitiesTable
881	Classes of financial liabilities [axis]	Axis			ifrs-full:ClassesOfFinancialLiabilitiesAxis
882	Financing liabilities [Member]	Member			ifrs-full:FinancialLiabilitiesMember
883	Trade accounts and notes payable [Member]	Member			hmc:TradeAccountsAndNotesPayableMember
884	Other [member]	Member			hmc:OtherTradePayablesMember
885	Disclosure of financial liabilities [line items]	LineItems			ifrs-full:DisclosureOfFinancialLiabilitiesLineItems
886	Trade payables	Concept (Monetary)	As Of	Credit	ifrs-full:TradeAndOtherCurrentPayablesToTradeSuppliers
887	1094 - Disclosure - Financing Liabilities - Financing Liabilities Presented in Current Liabilities (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureFinancingLiabilitiesFinancingLiabilitiesPresentedInCurrentLiabilities
888	Disclosure of detailed information about borrowings [table]	Table	*	*	ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsTable
889	Borrowings by name [axis]	Axis			ifrs-full:BorrowingsByNameAxis
890	Borrowings by name [member]	Member			ifrs-full:BorrowingsByNameMember
891	Commercial paper [member]	Member			hmc:CommercialPaper1Member
892	Loans [member]	Member			hmc:Loans1Member
893	Medium-term notes [member]	Member			hmc:MediumTermNotes1Member
894	Asset-backed securities [member]	Member			ifrs-full:AssetbackedFinancingsMember
895	Disclosure of detailed information about borrowings [line items]	LineItems			ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsLineItems
896	Current financing liabilities	Concept (Monetary)	As Of	Credit	ifrs-full:ShorttermBorrowings
897	Reclassification from non-current liabilities (Current portion)	Concept (Monetary)	As Of	Credit	ifrs-full:CurrentPortionOfLongtermBorrowings
898	Total	Concept (Monetary)	As Of	Credit	ifrs-full:CurrentBorrowingsAndCurrentPortionOfNoncurrentBorrowings
899	1095 - Disclosure - Financing Liabilities - Weighted Average Interest Rates for Financing Liabilities Presented in Current Liabilities (Excluding Reclassification from Non-current Liabilities) (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureFinancingLiabilitiesWeightedAverageInterestRatesForFinancingLiabilitiesPresentedInCurrentLiabilitiesExcludingReclassificationFromNoncurrentLiabilities
900	Disclosure of detailed information about borrowings [table]	Table	*	*	ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsTable
901	Classes of financial instruments [axis]	Axis			ifrs-full:ClassesOfFinancialInstrumentsAxis
902	Financial instruments, class [member]	Member			ifrs-full:ClassesOfFinancialInstrumentsMember
903	Current borrowings [member]	Member			hmc:CurrentBorrowingsMember
904	Range [axis]	Axis			ifrs-full:RangeAxis
905	Ranges [member]	Member			ifrs-full:RangesMember
906	Weighted average [member]	Member			ifrs-full:WeightedAverageMember
907	Disclosure of detailed information about borrowings [line items]	LineItems			ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsLineItems
908	Weighted average interest rate	Concept (Percent)	As Of		ifrs-full:BorrowingsInterestRate
909	1096 - Disclosure - Financing Liabilities - Financing Liabilities Presented in Non-current Liabilities (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureFinancingLiabilitiesFinancingLiabilitiesPresentedInNoncurrentLiabilities
910	Disclosure of detailed information about borrowings [table]	Table	*	*	ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsTable
911	Borrowings by name [axis]	Axis			ifrs-full:BorrowingsByNameAxis
912	Borrowings by name [member]	Member			ifrs-full:BorrowingsByNameMember
913	Loans [member]	Member			hmc:Loans1Member
914	Medium-term notes [member]	Member			hmc:MediumTermNotes1Member
915	Corporate bonds [member]	Member			hmc:CorporateBondsMember
916	Asset-backed securities [member]	Member			ifrs-full:AssetbackedFinancingsMember
917	Disclosure of detailed information about borrowings [line items]	LineItems			ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsLineItems
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919	Reclassification to current liabilities (Current portion)	Concept (Monetary)	As Of	Credit	ifrs-full:CurrentPortionOfLongtermBorrowings
920	Total	Concept (Monetary)	As Of	Credit	ifrs-full:LongtermBorrowings
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922	Disclosure of financial instruments by type of interest rate [table]	Table	*	*	ifrs-full:DisclosureOfFinancialInstrumentsByTypeOfInterestRateTable
923	Classes of financial instruments [axis]	Axis			ifrs-full:ClassesOfFinancialInstrumentsAxis
924	Financial instruments, class [member]	Member			ifrs-full:ClassesOfFinancialInstrumentsMember
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927	Borrowings by name [member]	Member			ifrs-full:BorrowingsByNameMember
928	Loans [member]	Member			hmc:Loans1Member
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930	Corporate bonds [member]	Member			hmc:CorporateBondsMember
931	Asset-backed securities [member]	Member			ifrs-full:AssetbackedFinancingsMember
932	Range [axis]	Axis			ifrs-full:RangeAxis
933	Ranges [member]	Member			ifrs-full:RangesMember
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935	Top of range [member]	Member			ifrs-full:TopOfRangeMember
936	Disclosure of financial instruments by type of interest rate [line items]	LineItems			ifrs-full:DisclosureOfFinancialInstrumentsByTypeOfInterestRateLineItems
937	Interest rate	Concept (Percent)	As Of		ifrs-full:BorrowingsInterestRate
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940	Implied Table	Table	*	*	implied:Table
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943	Receivables from financial services	Concept (Monetary)	As Of	Debit	hmc:ReceivablesFromFinancialServicesPledgedAsSecurityForLiabilities
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945	Property, plant and equipment	Concept (Monetary)	As Of	Debit	ifrs-full:PropertyPlantAndEquipmentPledgedAsSecurity
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947	1099 - Disclosure - Financing Liabilities - The Changes in Liabilities Arising from Financing Activities (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureFinancingLiabilitiesTheChangesInLiabilitiesArisingFromFinancingActivities
948	Disclosure of reconciliation of liabilities arising from financing activities [table]	Table	*	*	ifrs-full:DisclosureOfReconciliationOfLiabilitiesArisingFromFinancingActivitiesTable
949	Liabilities arising from financing activities [axis]	Axis			ifrs-full:LiabilitiesArisingFromFinancingActivitiesAxis
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951	Short-term financing liabilities [member]	Member			ifrs-full:ShorttermBorrowingsMember
952	Long-term financing liabilities [member]	Member			ifrs-full:LongtermBorrowingsMember
953	Lease obligations [member]	Member			ifrs-full:LeaseLiabilitiesMember
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955	Disclosure of reconciliation of liabilities arising from financing activities [line items]	LineItems			ifrs-full:DisclosureOfReconciliationOfLiabilitiesArisingFromFinancingActivitiesLineItems
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960	Non-cash changes, Changes in foreign currency exchange rates	Concept (Monetary)	For Period	Credit	ifrs-full:IncreaseDecreaseThroughEffectOfChangesInForeignExchangeRatesLiabilitiesArisingFromFinancingActivities
961	Non-cash changes, Changes in fair value	Concept (Monetary)	For Period	Credit	ifrs-full:IncreaseDecreaseThroughChangesInFairValuesLiabilitiesArisingFromFinancingActivities
962	Non-cash changes, Other	Concept (Monetary)	For Period	Credit	ifrs-full:IncreaseDecreaseThroughOtherChangesLiabilitiesArisingFromFinancingActivities
963	Changes in liabilities arising from financing activities, ending balance	Concept (Monetary)	As Of	Credit	ifrs-full:LiabilitiesArisingFromFinancingActivities
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969	Financial liabilities measured at fair value through profit or loss [member]	Member			ifrs-full:FinancialLiabilitiesAtFairValueThroughProfitOrLossCategoryMember
970	Classes of financial liabilities [axis]	Axis			ifrs-full:ClassesOfFinancialLiabilitiesAxis
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974	Derivatives [member]	Member			ifrs-full:DerivativesMember
975	Disclosure of financial liabilities [line items]	LineItems			ifrs-full:DisclosureOfFinancialLiabilitiesLineItems
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977	Current liabilities	Concept (Monetary)	As Of	Credit	ifrs-full:OtherCurrentFinancialLiabilities
978	Non-current liabilities	Concept (Monetary)	As Of	Credit	ifrs-full:OtherNoncurrentFinancialLiabilities
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980	1101 - Disclosure - Provisions - Components of and Changes in Provisions (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureProvisionsComponentsOfAndChangesInProvisions
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982	Classes of other provisions [axis]	Axis			ifrs-full:ClassesOfProvisionsAxis
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988	Provision	Concept (Monetary)	For Period	Credit	ifrs-full:AdditionalProvisionsOtherProvisions
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991	Exchange differences on translating foreign operations	Concept (Monetary)	For Period	Credit	ifrs-full:IncreaseDecreaseThroughNetExchangeDifferencesOtherProvisions
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993	1102 - Disclosure - Provisions - Current Liabilities and Non-current Liabilities of Provisions (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureProvisionsCurrentLiabilitiesAndNoncurrentLiabilitiesOfProvisions
994	Implied Table	Table	*	*	implied:Table
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997	Non-current liabilities	Concept (Monetary)	As Of	Credit	ifrs-full:OtherLongtermProvisions
998	Total	Concept (Monetary)	As Of	Credit	ifrs-full:OtherProvisions
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1000	Disclosure of defined benefit plans [table]	Table	*	*	ifrs-full:DisclosureOfDefinedBenefitPlansTable
1001	Defined benefit plans [axis]	Axis			ifrs-full:DefinedBenefitPlansAxis
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1004	Foreign plans [member]	Member			ifrs-full:ForeignDefinedBenefitPlansMember
1005	Net defined benefit liability (asset) [axis]	Axis			ifrs-full:NetDefinedBenefitLiabilityAssetAxis
1006	Retirement benefit liabilities [member]	Member			ifrs-full:NetDefinedBenefitLiabilityAssetMember
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1011	Selling, general and administrative [member]	Member			us-gaap:SellingGeneralAndAdministrativeExpensesMember
1012	Research and development [member]	Member			hmc:ResearchAndDevelopmentMember
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1018	Expected contributions to pension plans	Concept (Monetary)	For Period	Credit	ifrs-full:EstimateOfContributionsExpectedToBePaidToPlan
1019	1104 - Disclosure - Employee Benefits - Changes in Present Value of Defined Benefit Obligations and Fair Value of Plan Assets (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureEmployeeBenefitsChangesInPresentValueOfDefinedBenefitObligationsAndFairValueOfPlanAssets
1020	Disclosure of net defined benefit liability (asset) [table]	Table	*	*	ifrs-full:DisclosureOfNetDefinedBenefitLiabilityAssetTable
1021	Net defined benefit liability (asset) [axis]	Axis			ifrs-full:NetDefinedBenefitLiabilityAssetAxis
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1023	Present value of defined benefit obligation [member]	Member			ifrs-full:PresentValueOfDefinedBenefitObligationMember
1024	Fair value of plan assets [member]	Member			ifrs-full:PlanAssetsMember
1025	Defined benefit plans [axis]	Axis			ifrs-full:DefinedBenefitPlansAxis
1026	Defined benefit plans [member]	Member			ifrs-full:DefinedBenefitPlansMember
1027	Japanese plans [member]	Member			ifrs-full:DomesticDefinedBenefitPlansMember
1028	Foreign plans [member]	Member			ifrs-full:ForeignDefinedBenefitPlansMember
1029	Disclosure of net defined benefit liability (asset) [line items]	LineItems			ifrs-full:DisclosureOfNetDefinedBenefitLiabilityAssetLineItems
1030	Balance at beginning of year	Concept (Monetary)	As Of	Credit	ifrs-full:LiabilityAssetOfDefinedBenefitPlans
1031	Current service cost	Concept (Monetary)	For Period	Credit	ifrs-full:CurrentServiceCostNetDefinedBenefitLiabilityAsset
1032	Past service cost	Concept (Monetary)	For Period	Credit	ifrs-full:PastServiceCostNetDefinedBenefitLiabilityAsset
1033	Interest cost (income)	Concept (Monetary)	For Period	Credit	ifrs-full:InterestExpenseIncomeNetDefinedBenefitLiabilityAsset
1034	Actual return on plan assets, excluding interest income	Concept (Monetary)	For Period	Debit	ifrs-full:ReturnOnPlanAssetsNetDefinedBenefitLiabilityAsset
1035	Employer contributions	Concept (Monetary)	For Period	Debit	ifrs-full:ContributionsToPlanByEmployerNetDefinedBenefitLiabilityAsset
1036	Plan participants' contributions	Concept (Monetary)	For Period	Debit	ifrs-full:ContributionsToPlanByPlanParticipantsNetDefinedBenefitLiabilityAsset
1037	Transfer to defined contribution plan	Concept (Monetary)	For Period	Credit	ifrs-full:TransfersFromToOtherRetirementBenefitPlans
1038	Remeasurements:	Abstract			ifrs-full:GainLossOnRemeasurementOfNetDefinedBenefitLiabilityAssetAbstract
1039	Changes in demographic assumptions	Concept (Monetary)	For Period	Debit	ifrs-full:ActuarialGainsLossesArisingFromChangesInDemographicAssumptionsNetDefinedBenefitLiabilityAsset
1040	Changes in financial assumptions	Concept (Monetary)	For Period	Debit	ifrs-full:ActuarialGainsLossesArisingFromChangesInFinancialAssumptionsNetDefinedBenefitLiabilityAsset
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1043	Exchange differences on translating foreign operations	Concept (Monetary)	For Period	Credit	ifrs-full:IncreaseDecreaseThroughChangesInForeignExchangeRatesNetDefinedBenefitLiabilityAsset
1044	Balance at end of year	Concept (Monetary)	As Of	Credit	ifrs-full:LiabilityAssetOfDefinedBenefitPlans
1045	Net defined benefit liabilities	Concept (Monetary)	As Of	Debit	ifrs-full:SurplusDeficitInPlan
1046	1105 - Disclosure - Employee Benefits - Fair Value of Japanese and Foreign Pension Plan Assets By Asset Category (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureEmployeeBenefitsFairValueOfJapaneseAndForeignPensionPlanAssetsByAssetCategory
1047	Disclosure of fair value of plan assets [table]	Table	*	*	ifrs-full:DisclosureOfFairValueOfPlanAssetsTable
1048	Defined benefit plans [axis]	Axis			ifrs-full:DefinedBenefitPlansAxis
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1050	Japanese plans [member]	Member			ifrs-full:DomesticDefinedBenefitPlansMember
1051	Foreign plans [member]	Member			ifrs-full:ForeignDefinedBenefitPlansMember
1052	Levels of fair value hierarchy [axis]	Axis			ifrs-full:LevelsOfFairValueHierarchyAxis
1053	All levels of fair value hierarchy [member]	Member			ifrs-full:AllLevelsOfFairValueHierarchyMember
1054	Level 1 [member]	Member			ifrs-full:Level1OfFairValueHierarchyMember
1055	Unquoted, Market price in active market [member]	Member			ifrs-full:Level2And3OfFairValueHierarchyMember
1056	Geographical areas [axis]	Axis			ifrs-full:GeographicalAreasAxis
1057	Geographical areas [member]	Member			ifrs-full:GeographicalAreasMember
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1059	United States [member]	Member			country:US
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1061	Classes of assets [axis]	Axis			ifrs-full:ClassesOfAssetsAxis
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1067	Disclosure of fair value of plan assets [line items]	LineItems			ifrs-full:DisclosureOfFairValueOfPlanAssetsLineItems
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1069	Equity securities	Concept (Monetary)	As Of	Debit	ifrs-full:EquityInstrumentsAmountContributedToFairValueOfPlanAssets
1070	Debt securities	Concept (Monetary)	As Of	Debit	ifrs-full:DebtInstrumentsAmountContributedToFairValueOfPlanAssets
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1072	Separate accounts	Concept (Monetary)	As Of	Debit	hmc:SeparateAccountOfLifeInsuranceCompaniesContributedToFairValueOfPlanAssets
1073	Pooled funds	Concept (Monetary)	As Of	Debit	ifrs-full:InvestmentFundsAmountContributedToFairValueOfPlanAssets
1074	Other	Concept (Monetary)	As Of	Debit	ifrs-full:OtherAssetsAmountContributedToFairValueOfPlanAssets
1075	Total	Concept (Monetary)	As Of	Debit	ifrs-full:PlanAssetsAtFairValue
1076	1106 - Disclosure - Employee Benefits - Significant Actuarial Assumptions Used to Determine Present Value of Defined Benefit Obligations (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureEmployeeBenefitsSignificantActuarialAssumptionsUsedToDeterminePresentValueOfDefinedBenefitObligations
1077	Disclosure of defined benefit plans [table]	Table	*	*	ifrs-full:DisclosureOfDefinedBenefitPlansTable
1078	Defined benefit plans [axis]	Axis			ifrs-full:DefinedBenefitPlansAxis
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1080	Japanese plans [member]	Member			ifrs-full:DomesticDefinedBenefitPlansMember
1081	Foreign plans [member]	Member			ifrs-full:ForeignDefinedBenefitPlansMember
1082	Range [axis]	Axis			ifrs-full:RangeAxis
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1086	Disclosure of defined benefit plans [line items]	LineItems			ifrs-full:DisclosureOfDefinedBenefitPlansLineItems
1087	Discount rate	Concept (Percent)	As Of		ifrs-full:ActuarialAssumptionOfDiscountRates
1088	Rate of salary increase	Concept (Percent)	As Of		ifrs-full:ActuarialAssumptionOfExpectedRatesOfSalaryIncreases
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1090	Disclosure of sensitivity analysis for actuarial assumptions [table]	Table	*	*	ifrs-full:DisclosureOfSensitivityAnalysisForActuarialAssumptionsTable
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1101	1108 - Disclosure - Employee Benefits - Effects on Defined Benefit Obligations Due to Increase or Decrease in Discount Rate (Parenthetical) (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureEmployeeBenefitsEffectsOnDefinedBenefitObligationsDueToIncreaseOrDecreaseInDiscountRateParenthetical
1102	Disclosure of sensitivity analysis for actuarial assumptions [table]	Table	*	*	ifrs-full:DisclosureOfSensitivityAnalysisForActuarialAssumptionsTable
1103	Actuarial assumptions [axis]	Axis			ifrs-full:ActuarialAssumptionsAxis
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1105	Discount rates [member]	Member			ifrs-full:ActuarialAssumptionOfDiscountRatesMember
1106	Disclosure of sensitivity analysis for actuarial assumptions [line items]	LineItems			ifrs-full:DisclosureOfSensitivityAnalysisForActuarialAssumptionsLineItems
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1108	Percentage of increase in the discount rate	Concept (Percent)	As Of		ifrs-full:PercentageOfReasonablyPossibleIncreaseInActuarialAssumption
1109	1109 - Disclosure - Employee Benefits - Weighted Average Duration of Defined Benefit Obligations (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureEmployeeBenefitsWeightedAverageDurationOfDefinedBenefitObligations
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1111	Defined benefit plans [axis]	Axis			ifrs-full:DefinedBenefitPlansAxis
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1114	Foreign plans [member]	Member			ifrs-full:ForeignDefinedBenefitPlansMember
1115	Disclosure of defined benefit plans [line items]	LineItems			ifrs-full:DisclosureOfDefinedBenefitPlansLineItems
1116	Weighted average duration of defined benefit obligations	Concept (Decimal)	For Period		ifrs-full:WeightedAverageDurationOfDefinedBenefitObligation
1117	1110 - Disclosure - Employee Benefits - Personnel Expenses Included in Consolidated Statements of Income (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureEmployeeBenefitsPersonnelExpensesIncludedInConsolidatedStatementsOfIncome
1118	Implied Table	Table	*	*	implied:Table
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1121	1111 - Disclosure - Equity - Financial Liabilities and Equity (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureEquityFinancialLiabilitiesAndEquity
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1126	1112 - Disclosure - Equity - Total Number of Shares Authorized and Issued (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureEquityTotalNumberOfSharesAuthorizedAndIssued
1127	Implied Table	Table	*	*	implied:Table
1128	Equity [abstract]	Abstract			ifrs-full:EquityAbstract
1129	Total number of authorized shares	Abstract			hmc:NumberOfSharesAuthorisedAbstract
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1135	1113 - Disclosure - Equity - Additional Information (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureEquityAdditionalInformation
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1140	Disclosure of classes of share capital [line items]	LineItems			ifrs-full:DisclosureOfClassesOfShareCapitalLineItems
1141	Minimum percentage of paid-in amount or proceeds of issuance of shares allowed to be incorporated in common stock	Concept (Percent)	For Period		hmc:PercentageOfPaidinAmountOrProceedsOfIssuanceOfSharesAllowedToBeIncorporatedInCommonStock
1142	Percentage of cash dividends from retained earnings shall be appropriated as a capital reserve	Concept (Percent)	For Period		hmc:PercentageOfCashDividendsFromRetainedEarningsShallBeAppropriatedAsCapitalReserve
1143	Percentage of capital reserve and legal reserve to common stock	Concept (Percent)	For Period		hmc:PercentageOfCapitalReserveAndLegalReserveToCommonStock
1144	1114 - Disclosure - Equity - Total Number of Treasury Stock Held (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureEquityTotalNumberOfTreasuryStockHeld
1145	Disclosure of classes of share capital [table]	Table	*	*	ifrs-full:DisclosureOfClassesOfShareCapitalTable
1146	Components of equity [axis]	Axis			ifrs-full:ComponentsOfEquityAxis
1147	Equity [member]	Member			ifrs-full:EquityMember
1148	Treasury stock [member]	Member			ifrs-full:TreasurySharesMember
1149	Disclosure of classes of share capital [line items]	LineItems			ifrs-full:DisclosureOfClassesOfShareCapitalLineItems
1150	Common shares	Concept (Shares)	As Of		ifrs-full:NumberOfSharesIssued
1151	1115 - Disclosure - Equity - Changes in Other Components of Equity (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureEquityChangesInOtherComponentsOfEquity
1152	Disclosure of reserves within equity [table]	Table	*	*	ifrs-full:DisclosureOfReservesWithinEquityTable
1153	Components of equity [axis]	Axis			ifrs-full:ComponentsOfEquityAxis
1154	Equity [member]	Member			ifrs-full:EquityMember
1155	Remeasurements of defined benefit plans [member]	Member			ifrs-full:ReserveOfRemeasurementsOfDefinedBenefitPlansMember
1156	Net changes in revaluation of financial assets measured at fair value through other comprehensive income [member]	Member			ifrs-full:ReserveOfGainsAndLossesFromInvestmentsInEquityInstrumentsMember
1157	Exchange differences on translating foreign operations [member]	Member			ifrs-full:ReserveOfExchangeDifferencesOnTranslationMember
1158	Other components of equity [member]	Member			ifrs-full:OtherReservesMember
1159	Disclosure of reserves within equity [line items]	LineItems			ifrs-full:DisclosureOfReservesWithinEquityLineItems
1160	Beginning balance	Concept (Monetary)	As Of	Credit	ifrs-full:Equity
1161	Adjustment during the year	Concept (Monetary)	For Period	Credit	ifrs-full:OtherComprehensiveIncome
1162	Reclassification to retained earnings	Concept (Monetary)	For Period	Credit	hmc:IncreaseDecreaseThroughReclassificationToRetainedEarningsEquity
1163	Ending balance	Concept (Monetary)	As Of	Credit	ifrs-full:Equity
1164	1116 - Disclosure - Equity - Each Component of Other Comprehensive Income and Related Tax Effect Including Non-controlling Interests (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureEquityEachComponentOfOtherComprehensiveIncomeAndRelatedTaxEffectIncludingNoncontrollingInterests
1165	Implied Table	Table	*	*	implied:Table
1166	Statement of comprehensive income [abstract]	Abstract			ifrs-full:StatementOfComprehensiveIncomeAbstract
1167	Items that will not be reclassified to profit or loss, Before-tax:	Abstract			ifrs-full:ComponentsOfOtherComprehensiveIncomeThatWillNotBeReclassifiedToProfitOrLossBeforeTaxAbstract
1168	Remeasurements of defined benefit plans, Net changes, Before-tax	Concept (Monetary)	For Period	Credit	ifrs-full:OtherComprehensiveIncomeBeforeTaxGainsLossesOnRemeasurementsOfDefinedBenefitPlans
1169	Net changes in revaluation of financial assets measured at fair value through other comprehensive income, Net changes, Before-tax	Concept (Monetary)	For Period	Credit	ifrs-full:OtherComprehensiveIncomeBeforeTaxGainsLossesFromInvestmentsInEquityInstruments
1170	Share of other comprehensive income of investments accounted for using the equity method, Net changes, Before-tax	Concept (Monetary)	For Period	Credit	ifrs-full:ShareOfOtherComprehensiveIncomeOfAssociatesAndJointVenturesAccountedForUsingEquityMethodThatWillNotBeReclassifiedToProfitOrLossBeforeTax
1171	Items that may be reclassified subsequently to profit or loss, Before-tax:	Abstract			ifrs-full:ComponentsOfOtherComprehensiveIncomeThatWillBeReclassifiedToProfitOrLossBeforeTaxAbstract
1172	Exchange differences on translating foreign operations, Amount incurred during the year, Before-tax	Concept (Monetary)	For Period	Credit	ifrs-full:GainsLossesOnExchangeDifferencesOnTranslationBeforeTax
1173	Exchange differences on translating foreign operations, Reclassification to profit or loss, Before-tax	Concept (Monetary)	For Period	Debit	ifrs-full:ReclassificationAdjustmentsOnExchangeDifferencesOnTranslationBeforeTax
1174	Exchange differences on translating foreign operations, Net changes, Before-tax	Concept (Monetary)	For Period	Credit	ifrs-full:OtherComprehensiveIncomeBeforeTaxExchangeDifferencesOnTranslation
1175	Share of other comprehensive income of investments accounted for using the equity method, Amount incurred during the year, Before-tax	Concept (Monetary)	For Period	Credit	hmc:ShareOfOtherComprehensiveIncomeOfAssociatesAndJointVenturesAccountedForUsingEquityMethodThatWillBeReclassifiedToProfitOrLossChangesBeforeReclassificationBeforeTax
1176	Share of other comprehensive income of investments accounted for using the equity method, Reclassification to profit or loss, Before-tax	Concept (Monetary)	For Period	Debit	hmc:ShareOfOtherComprehensiveIncomeOfAssociatesAndJointVenturesAccountedForUsingEquityMethodThatWillBeReclassifiedToProfitOrLossReclassifiedToProfitOrLossBeforeTax
1177	Share of other comprehensive income of investments accounted for using the equity method, Net changes, Before-tax	Concept (Monetary)	For Period	Credit	ifrs-full:ShareOfOtherComprehensiveIncomeOfAssociatesAndJointVenturesAccountedForUsingEquityMethodThatWillBeReclassifiedToProfitOrLossBeforeTax
1178	Total other comprehensive income, Before-tax	Concept (Monetary)	For Period	Credit	ifrs-full:OtherComprehensiveIncomeBeforeTax
1179	Items that will not be reclassified to profit or loss, Tax benefit (expense):	Abstract			ifrs-full:IncomeTaxRelatingToComponentsOfOtherComprehensiveIncomeThatWillNotBeReclassifiedToProfitOrLossAbstract
1180	Remeasurements of defined benefit plans, Net changes, Tax benefit (expense)	Concept (Monetary)	For Period	Debit	ifrs-full:IncomeTaxRelatingToRemeasurementsOfDefinedBenefitPlansOfOtherComprehensiveIncome
1181	Net changes in revaluation of financial assets measured at fair value through other comprehensive income, Net changes, Tax benefit (expense)	Concept (Monetary)	For Period	Debit	ifrs-full:IncomeTaxRelatingToInvestmentsInEquityInstrumentsOfOtherComprehensiveIncome
1182	Share of other comprehensive income of investments accounted for using the equity method, Net changes, Tax benefit (expense)	Concept (Monetary)	For Period	Debit	ifrs-full:IncomeTaxRelatingToShareOfOtherComprehensiveIncomeOfAssociatesAndJointVenturesAccountedForUsingEquityMethodThatWillNotBeReclassifiedToProfitOrLoss
1183	Items that may be reclassified subsequently to profit or loss, Tax benefit (expense):	Abstract			ifrs-full:IncomeTaxRelatingToComponentsOfOtherComprehensiveIncomeThatWillBeReclassifiedToProfitOrLossAbstract
1184	Exchange differences on translating foreign operations, Amount incurred during the year, Tax benefit (expense)	Concept (Monetary)	For Period	Debit	hmc:GainsLossesOnExchangeDifferencesOnTranslationTax
1185	Exchange differences on translating foreign operations, Reclassification to profit or loss, Tax benefit (expense)	Concept (Monetary)	For Period	Credit	hmc:ReclassificationAdjustmentsOnExchangeDifferencesOnTranslationTax
1186	Exchange differences on translating foreign operations, Net changes, Tax benefit (expense)	Concept (Monetary)	For Period	Debit	ifrs-full:IncomeTaxRelatingToExchangeDifferencesOnTranslationOfOtherComprehensiveIncome
1187	Share of other comprehensive income of investments accounted for using the equity method, Amount incurred during the year, Tax benefit (expense)	Concept (Monetary)	For Period	Debit	hmc:ShareOfOtherComprehensiveIncomeOfAssociatesAndJointVenturesAccountedForUsingEquityMethodThatWillBeReclassifiedToProfitOrLossChangesBeforeReclassificationTax
1188	Share of other comprehensive income of investments accounted for using the equity method, Reclassification to profit or loss, Tax benefit (expense)	Concept (Monetary)	For Period	Credit	hmc:ShareOfOtherComprehensiveIncomeOfAssociatesAndJointVenturesAccountedForUsingEquityMethodThatWillBeReclassifiedToProfitOrLossTax
1189	Share of other comprehensive income of investments accounted for using the equity method, Net changes, Tax benefit (expense)	Concept (Monetary)	For Period	Debit	ifrs-full:IncomeTaxRelatingToShareOfOtherComprehensiveIncomeOfAssociatesAndJointVenturesAccountedForUsingEquityMethodThatWillBeReclassifiedToProfitOrLoss
1190	Total other comprehensive income, Tax benefit (expense)	Concept (Monetary)	For Period		ifrs-full:IncomeTaxRelatingToComponentsOfOtherComprehensiveIncome
1191	Items that will not be reclassified to profit or loss, Net-of-tax:	Abstract			ifrs-full:ComponentsOfOtherComprehensiveIncomeThatWillNotBeReclassifiedToProfitOrLossNetOfTaxAbstract
1192	Remeasurements of defined benefit plans, Net changes, Net-of-tax	Concept (Monetary)	For Period	Credit	ifrs-full:OtherComprehensiveIncomeNetOfTaxGainsLossesOnRemeasurementsOfDefinedBenefitPlans
1193	Net changes in revaluation of financial assets measured at fair value through other comprehensive income, Net changes, Net-of-tax	Concept (Monetary)	For Period	Credit	ifrs-full:OtherComprehensiveIncomeNetOfTaxGainsLossesFromInvestmentsInEquityInstruments
1194	Share of other comprehensive income of investments accounted for using the equity method, Net changes, Net-of-tax	Concept (Monetary)	For Period	Credit	ifrs-full:ShareOfOtherComprehensiveIncomeOfAssociatesAndJointVenturesAccountedForUsingEquityMethodThatWillNotBeReclassifiedToProfitOrLossNetOfTax
1195	Items that may be reclassified subsequently to profit or loss, Net-of-tax:	Abstract			ifrs-full:ComponentsOfOtherComprehensiveIncomeThatWillBeReclassifiedToProfitOrLossNetOfTaxAbstract
1196	Exchange differences on translating foreign operations, Amount incurred during the year, Net-of-tax	Concept (Monetary)	For Period	Credit	ifrs-full:GainsLossesOnExchangeDifferencesOnTranslationNetOfTax
1197	Exchange differences on translating foreign operations, Reclassification to profit or loss, Net-of-tax	Concept (Monetary)	For Period	Debit	ifrs-full:ReclassificationAdjustmentsOnExchangeDifferencesOnTranslationNetOfTax
1198	Exchange differences on translating foreign operations, Net changes, Net-of-tax	Concept (Monetary)	For Period	Credit	ifrs-full:OtherComprehensiveIncomeNetOfTaxExchangeDifferencesOnTranslation
1199	Share of other comprehensive income of investments accounted for using the equity method, Amount incurred during the year, Net-of-tax	Concept (Monetary)	For Period	Credit	hmc:ShareOfOtherComprehensiveIncomeOfAssociatesAndJointVenturesAccountedForUsingEquityMethodThatWillBeReclassifiedToProfitOrLossChangesBeforeReclassificationNetOfTax
1200	Share of other comprehensive income of investments accounted for using the equity method, Reclassification to profit or loss, Net-of-tax	Concept (Monetary)	For Period	Debit	hmc:ShareOfOtherComprehensiveIncomeOfAssociatesAndJointVenturesAccountedForUsingEquityMethodThatWillBeReclassifiedToProfitOrLossReclassifiedToProfitOrLossNetOfTax
1201	Share of other comprehensive income of investments accounted for using the equity method, Net changes, Net-of-tax	Concept (Monetary)	For Period	Credit	ifrs-full:ShareOfOtherComprehensiveIncomeOfAssociatesAndJointVenturesAccountedForUsingEquityMethodThatWillBeReclassifiedToProfitOrLossNetOfTax
1202	Total other comprehensive income, Net-of-tax	Concept (Monetary)	For Period	Credit	ifrs-full:OtherComprehensiveIncome
1203	1117 - Disclosure - Equity - Components of Other Comprehensive Income Included in Non-controlling Interests (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureEquityComponentsOfOtherComprehensiveIncomeIncludedInNoncontrollingInterests
1204	Disclosure of analysis of other comprehensive income by item [table]	Table	*	*	ifrs-full:DisclosureOfAnalysisOfOtherComprehensiveIncomeByItemTable
1205	Components of equity [axis]	Axis			ifrs-full:ComponentsOfEquityAxis
1206	Equity [member]	Member			ifrs-full:EquityMember
1207	Non-controlling interests [Member]	Member			ifrs-full:NoncontrollingInterestsMember
1208	Disclosure of analysis of other comprehensive income by item [line items]	LineItems			ifrs-full:DisclosureOfAnalysisOfOtherComprehensiveIncomeByItemLineItems
1209	Remeasurements of defined benefit plans	Concept (Monetary)	For Period	Credit	ifrs-full:OtherComprehensiveIncomeNetOfTaxGainsLossesOnRemeasurementsOfDefinedBenefitPlans
1210	Net changes in revaluation of financial assets measured at fair value through other comprehensive income	Concept (Monetary)	For Period	Credit	ifrs-full:OtherComprehensiveIncomeNetOfTaxGainsLossesFromInvestmentsInEquityInstruments
1211	Exchange differences on translating foreign operations	Concept (Monetary)	For Period	Credit	ifrs-full:OtherComprehensiveIncomeNetOfTaxExchangeDifferencesOnTranslation
1212	Total	Concept (Monetary)	For Period	Credit	ifrs-full:OtherComprehensiveIncome
1213	1118 - Disclosure - Equity - Dividends from Retained Earnings (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureEquityDividendsFromRetainedEarnings
1214	Implied Table	Table	*	*	implied:Table
1215	Dividends 1 [Abstract]	Abstract			hmc:Dividends1Abstract
1216	Dividend payout, Total amount of dividends (millions of yen)	Concept (Monetary)	For Period	Debit	ifrs-full:DividendsPaidOrdinaryShares
1217	Dividend payout, Dividend per share (yen)	Concept (Share)	For Period		ifrs-full:DividendsPaidOrdinarySharesPerShare
1218	Dividend payout, Record date	Concept (Date)	For Period		hmc:DividendsRecordDate
1219	Dividend payout, Effective date	Concept (Date)	For Period		hmc:DividendsEffectiveDate
1220	Dividends payable, Total amount of dividends (millions of yen)	Concept (Monetary)	For Period		ifrs-full:DividendsProposedOrDeclaredBeforeFinancialStatementsAuthorisedForIssueButNotRecognisedAsDistributionToOwners
1221	Dividends payable, Dividend per share (yen)	Concept (Share)	For Period		ifrs-full:DividendsProposedOrDeclaredBeforeFinancialStatementsAuthorisedForIssueButNotRecognisedAsDistributionToOwnersPerShare
1222	Dividends payable, Record date	Concept (Date)	For Period		hmc:DividendsProposedOrDeclaredBeforeFinancialStatementsAuthorisedForIssueButNotRecognisedAsDistributionToOwnersRecordDate
1223	Dividends payable, Effective date	Concept (Date)	For Period		hmc:DividendsProposedOrDeclaredBeforeFinancialStatementsAuthorisedForIssueButNotRecognisedAsDistributionToOwnersEffectiveDate
1224	1119 - Disclosure - Sales Revenue - Summary of Sales Revenue (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureSalesRevenueSummaryOfSalesRevenue
1225	Implied Table	Table	*	*	implied:Table
1226	Revenue [abstract]	Abstract			ifrs-full:RevenueAbstract
1227	Sales of products	Concept (Monetary)	For Period	Credit	ifrs-full:RevenueFromSaleOfGoods
1228	Revenue from financial services	Concept (Monetary)	For Period	Credit	ifrs-full:RevenueFromRenderingOfServices
1229	Total	Concept (Monetary)	For Period	Credit	ifrs-full:Revenue
1230	1120 - Disclosure - Research and Development - Summary of Research and Development Costs (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureResearchAndDevelopmentSummaryOfResearchAndDevelopmentCosts
1231	Implied Table	Table	*	*	implied:Table
1232	Material income and expense [abstract]	Abstract			ifrs-full:MaterialIncomeAndExpenseAbstract
1233	Research and development expenditures incurred during the reporting period	Concept (Monetary)	For Period	Debit	hmc:ResearchAndDevelopmentIncentivesReceivableDuringReportingPeriod
1234	Amount capitalized	Concept (Monetary)	For Period	Credit	ifrs-full:OtherWorkPerformedByEntityAndCapitalised
1235	Amortization of capitalized development costs	Concept (Monetary)	For Period	Debit	hmc:AmortizationOfCapitalizedDevelopmentExpenditure
1236	Total	Concept (Monetary)	For Period	Debit	ifrs-full:ResearchAndDevelopmentExpense
1237	1121 - Disclosure - Finance Income and Finance Costs - Summary of Finance Income and Finance Costs (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureFinanceIncomeAndFinanceCostsSummaryOfFinanceIncomeAndFinanceCosts
1238	Implied Table	Table	*	*	implied:Table
1239	Material income and expense [abstract]	Abstract			ifrs-full:MaterialIncomeAndExpenseAbstract
1240	Interest income:	Abstract			hmc:FinancialIncomeAbstract
1241	Financial assets measured at amortized cost	Concept (Monetary)	For Period	Credit	ifrs-full:InterestIncomeForFinancialAssetsMeasuredAtAmortisedCost
1242	Financial assets measured at fair value through profit or loss	Concept (Monetary)	For Period	Credit	ifrs-full:InterestIncomeOnFinancialAssetsDesignatedAtFairValueThroughProfitOrLoss
1243	Total	Concept (Monetary)	For Period	Credit	ifrs-full:FinanceIncome
1244	Interest expense:	Abstract			ifrs-full:InterestCostsAbstract
1245	Financial liabilities measured at amortized cost	Concept (Monetary)	For Period	Debit	ifrs-full:InterestExpense
1246	Other, net:	Abstract			hmc:FinanceIncomeCostsOtherNetAbstract
1247	Dividends received:	Abstract			hmc:Dividends1Abstract
1248	Financial assets measured at fair value through other comprehensive income	Concept (Monetary)	For Period	Credit	ifrs-full:DividendsRecognisedForInvestmentsInEquityInstrumentsDesignatedAsMeasuredAtFairValueThroughOtherComprehensiveIncomeHeldAtEndOfReportingPeriod
1249	Financial assets measured at fair value through profit or loss	Concept (Monetary)	For Period	Credit	ifrs-full:RevenueFromDividends
1250	Gains (losses) on derivatives:	Abstract			ifrs-full:GainsLossesOnChangeInFairValueOfDerivativesAbstract
1251	Financial assets and financial liabilities measured at fair value through profit or loss	Concept (Monetary)	For Period	Credit	ifrs-full:GainsLossesOnChangeInFairValueOfDerivatives
1252	Gains (losses) on foreign exchange	Concept (Monetary)	For Period	Credit	ifrs-full:GainsLossesOnExchangeDifferencesOnTranslationRecognisedInProfitOrLoss
1253	Other	Concept (Monetary)	For Period	Credit	hmc:OtherFinanceIncomeCostOther
1254	Total	Concept (Monetary)	For Period	Credit	ifrs-full:OtherFinanceIncomeCost
1255	Total finance income and finance costs	Concept (Monetary)	For Period	Credit	ifrs-full:FinanceIncomeCost
1256	1122 - Disclosure - Income Taxes - Profit Before Income Taxes and Income Tax Expense (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureIncomeTaxesProfitBeforeIncomeTaxesAndIncomeTaxExpense
1257	Disclosure of income taxes [Table]	Table	*	*	hmc:DisclosureOfIncomeTaxesTable
1258	Geographical areas [axis]	Axis			ifrs-full:GeographicalAreasAxis
1259	Geographical areas [member]	Member			ifrs-full:GeographicalAreasMember
1260	Japan [member]	Member			ifrs-full:CountryOfDomicileMember
1261	Foreign [member]	Member			ifrs-full:ForeignCountriesMember
1262	Disclosure of income taxes [Line Items]	LineItems			hmc:DisclosureOfIncomeTaxesLineItems
1263	Profit (loss) before income taxes	Concept (Monetary)	For Period	Credit	ifrs-full:ProfitLossBeforeTax
1264	Income tax expense (benefit):	Abstract			hmc:IncomeTaxExpenseBenefitsAbstract
1265	Current taxes	Concept (Monetary)	For Period	Debit	ifrs-full:CurrentTaxExpenseIncome
1266	Deferred taxes	Concept (Monetary)	For Period	Debit	ifrs-full:DeferredTaxExpenseIncome
1267	Total	Concept (Monetary)	For Period	Debit	ifrs-full:IncomeTaxExpenseContinuingOperations
1268	1123 - Disclosure - Income Taxes - Additional Information (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureIncomeTaxesAdditionalInformation
1269	Disclosure of income taxes [Table]	Table	*	*	hmc:DisclosureOfIncomeTaxesTable
1270	Geographical areas [axis]	Axis			ifrs-full:GeographicalAreasAxis
1271	Geographical areas [member]	Member			ifrs-full:GeographicalAreasMember
1272	Japan [member]	Member			ifrs-full:CountryOfDomicileMember
1273	Foreign [member]	Member			ifrs-full:ForeignCountriesMember
1274	Range [axis]	Axis			ifrs-full:RangeAxis
1275	Ranges [member]	Member			ifrs-full:RangesMember
1276	Bottom of range [member]	Member			ifrs-full:BottomOfRangeMember
1277	Top of range [member]	Member			ifrs-full:TopOfRangeMember
1278	Disclosure of income taxes [Line Items]	LineItems			hmc:DisclosureOfIncomeTaxesLineItems
1279	Statutory income tax rate	Concept (Percent)	For Period		ifrs-full:ApplicableTaxRate
1280	Deferred tax assets recognized by entities that have suffered a loss in either the preceding or current period	Concept (Monetary)	As Of	Debit	ifrs-full:DeferredTaxAssetWhenUtilisationIsDependentOnFutureTaxableProfitsInExcessOfProfitsFromReversalOfTaxableTemporaryDifferencesAndEntityHasSufferedLossInJurisdictionToWhichDeferredTaxAssetRelates
1281	Aggregate amounts of temporary differences relating to investments in subsidiaries and interests in joint ventures for which deferred tax liabilities are not recognized	Concept (Monetary)	As Of		ifrs-full:TemporaryDifferencesAssociatedWithInvestmentsInSubsidiariesBranchesAndAssociatesAndInterestsInJointVentures
1282	1124 - Disclosure - Income Taxes - Reconciliation of Statutory Income Tax Rate to Average Effective Tax Rate (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureIncomeTaxesReconciliationOfStatutoryIncomeTaxRateToAverageEffectiveTaxRate
1283	Implied Table	Table	*	*	implied:Table
1284	Reconciliation of average effective tax rate and applicable tax rate [abstract]	Abstract			ifrs-full:ReconciliationOfAverageEffectiveTaxRateAndApplicableTaxRateAbstract
1285	Statutory income tax rate	Concept (Percent)	For Period		ifrs-full:ApplicableTaxRate
1286	Difference in statutory income tax rates of foreign subsidiaries	Concept (Percent)	For Period		ifrs-full:TaxRateEffectOfForeignTaxRates
1287	Effects of investments accounted for using the equity method	Concept (Percent)	For Period		hmc:TaxRateEffectOfInvestmentsAccountedForUsingTheEquityMethod
1288	Effects of undistributed earnings and withholding taxes on royalty	Concept (Percent)	For Period		hmc:TaxRateEffectOfUndistributedEarningsAndWithholdingTaxesOnRoyalty
1289	Changes in unrecognized deferred tax assets	Concept (Percent)	For Period		hmc:TaxRateEffectOfChangesInUnrecognizedDeferredTaxAssets
1290	Effects of income and expense not taxable and deductible for tax purpose	Concept (Percent)	For Period		hmc:TaxRateEffectOfIncomeAndExpenseNotTaxableAndDeductibleForTaxPurpose
1291	Effects of tax credit	Concept (Percent)	For Period		hmc:TaxRateEffectOfTaxCredits
1292	Other adjustments relating to prior years	Concept (Percent)	For Period		ifrs-full:TaxRateEffectOfAdjustmentsForCurrentTaxOfPriorPeriods
1293	Adjustments for the uncertain tax positions on income taxes	Concept (Percent)	For Period		hmc:TaxRateEffectOfAdjustmentsForUncertainTaxPositionsOnIncomeTaxes
1294	Transfer pricing tax refund	Concept (Percent)	For Period		hmc:TaxRateEffectOfTransferPricingTaxRefund
1295	Adjustments for the changes in income tax laws	Concept (Percent)	For Period		ifrs-full:TaxRateEffectFromChangeInTaxRate
1296	Other	Concept (Percent)	For Period		ifrs-full:OtherTaxRateEffectsForReconciliationBetweenAccountingProfitAndTaxExpenseIncome
1297	Average effective tax rate	Concept (Percent)	For Period		ifrs-full:AverageEffectiveTaxRate
1298	1125 - Disclosure - Income Taxes - Reconciliation of Statutory Income Tax Rate to Average Effective Tax Rate (Parenthetical) (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureIncomeTaxesReconciliationOfStatutoryIncomeTaxRateToAverageEffectiveTaxRateParenthetical
1299	Disclosure of income taxes [Table]	Table	*	*	hmc:DisclosureOfIncomeTaxesTable
1300	Geographical [Axis]	Axis			us-gaap:StatementGeographicalAxis
1301	Geographical [Domain]	Member			us-gaap:SegmentGeographicalDomain
1302	United States [member]	Member			country:US
1303	Scenario [Axis]	Axis			us-gaap:StatementScenarioAxis
1304	Scenario, Unspecified [Domain]	Member			us-gaap:ScenarioUnspecifiedDomain
1305	Scenario, Plan [Member]	Member			us-gaap:ScenarioPlanMember
1306	Disclosure of income taxes [Line Items]	LineItems			hmc:DisclosureOfIncomeTaxesLineItems
1307	Approximate statutory income tax rate related to approved amendments from the National Diet of Japan	Concept (Percent)	For Period		hmc:ApproximateApplicableTaxRateDueToApprovedAmendment
1308	Approximate revised statutory income tax rate related to approved amendments from the National Diet of Japan	Concept (Percent)	For Period		hmc:ApproximateRevisedApplicableTaxRateDueToApprovedAmendment
1309	Income tax expense decrease due to transfer pricing tax refund	Concept (Monetary)	For Period	Debit	hmc:TaxEffectOfTransferPricingTaxRefund
1310	Applicable tax rate	Concept (Percent)	For Period		ifrs-full:ApplicableTaxRate
1311	Average effective tax rate	Concept (Percent)	For Period		ifrs-full:AverageEffectiveTaxRate
1312	Decrease in income tax expenses	Concept (Monetary)	For Period	Debit	hmc:TaxCutsAndJobsActOf2017ChangeInTaxRateIncomeTaxExpenseBenefit
1313	1126 - Disclosure - Income Taxes - Components by Major Factor in Deferred Tax Assets and Deferred Tax Liabilities (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureIncomeTaxesComponentsByMajorFactorInDeferredTaxAssetsAndDeferredTaxLiabilities
1314	Disclosure of temporary difference, unused tax losses and unused tax credits [table]	Table	*	*	ifrs-full:DisclosureOfTemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsTable
1315	Carrying amount, accumulated depreciation, amortisation and impairment and gross carrying amount [axis]	Axis			ifrs-full:CarryingAmountAccumulatedDepreciationAmortisationAndImpairmentAndGrossCarryingAmountAxis
1316	Carrying amount [member]	Member			ifrs-full:CarryingAmountMember
1317	Gross carrying amount [member]	Member			ifrs-full:GrossCarryingAmountMember
1318	Assets and liabilities [axis]	Axis			ifrs-full:AssetsAndLiabilitiesAxis
1319	Assets and liabilities [member]	Member			ifrs-full:AssetsAndLiabilitiesMember
1320	Inventories [member]	Member			hmc:InventoryMember
1321	Accrued expenses [Member]	Member			hmc:AccruedExpensesMember
1322	Provisions [member]	Member			ifrs-full:OtherProvisionsMember
1323	Property, plant and equipment [member]	Member			ifrs-full:PropertyPlantAndEquipmentMember
1324	Intangible assets [Member]	Member			ifrs-full:IntangibleAssetsOtherThanGoodwillMember
1325	Retirement benefit liabilities [member]	Member			ifrs-full:NetDefinedBenefitLiabilityAssetMember
1326	Carryforward of unused tax losses [member]	Member			ifrs-full:UnusedTaxLossesMember
1327	Carryforward of unused tax credit [member]	Member			ifrs-full:UnusedTaxCreditsMember
1328	Other [Member]	Member			ifrs-full:OtherAssetsMember
1329	Other financial assets [member]	Member			hmc:OtherFinancialAssetMember
1330	Finance leases [Member]	Member			hmc:FinanceLeasesMember
1331	Operating leases [member]	Member			hmc:OperatingLeasesMember
1332	Undistributed earnings [member]	Member			hmc:UndistributedEarningsMember
1333	Other [Member]	Member			us-gaap:OtherLiabilitiesMember
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1351	Disclosure of temporary difference, unused tax losses and unused tax credits [line items]	LineItems			ifrs-full:DisclosureOfTemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsLineItems
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1400	1134 - Disclosure - Financial Risk Management - Interest Rate Risk Sensitivity Analysis (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureFinancialRiskManagementInterestRateRiskSensitivityAnalysis
1401	Disclosure of nature and extent of risks arising from financial instruments [table]	Table	*	*	ifrs-full:DisclosureOfNatureAndExtentOfRisksArisingFromFinancialInstrumentsTable
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1407	1135 - Disclosure - Financial Risk Management - Analysis of the Age of Receivables from Financial Services that are Past Due (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureFinancialRiskManagementAnalysisOfTheAgeOfReceivablesFromFinancialServicesThatArePastDue
1408	Disclosure of financial assets that are either past due or impaired [table]	Table	*	*	ifrs-full:DisclosureOfFinancialAssetsThatAreEitherPastDueOrImpairedTable
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1425	1136 - Disclosure - Financial Risk Management - Unused Portions of the Credit Facility (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureFinancialRiskManagementUnusedPortionsOfTheCreditFacility
1426	Disclosure of risk management strategy related to hedge accounting [table]	Table	*	*	ifrs-full:DisclosureOfRiskManagementStrategyRelatedToHedgeAccountingTable
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1434	1137 - Disclosure - Financial Risk Management - Unused Portions of the Committed Lines of Credit (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureFinancialRiskManagementUnusedPortionsOfTheCommittedLinesOfCredit
1435	Disclosure of risk management strategy related to hedge accounting [table]	Table	*	*	ifrs-full:DisclosureOfRiskManagementStrategyRelatedToHedgeAccountingTable
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1443	1138 - Disclosure - Financial Risk Management - Non-derivative Financial Liabilities by Maturity (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureFinancialRiskManagementNonderivativeFinancialLiabilitiesByMaturity
1444	Disclosure of maturity analysis for non-derivative financial liabilities [table]	Table	*	*	ifrs-full:DisclosureOfMaturityAnalysisForNonderivativeFinancialLiabilitiesTable
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1461	1139 - Disclosure - Financial Risk Management - Derivative Financial Liabilities by Maturity (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureFinancialRiskManagementDerivativeFinancialLiabilitiesByMaturity
1462	Disclosure of maturity analysis for derivative financial liabilities [table]	Table	*	*	ifrs-full:DisclosureOfMaturityAnalysisForDerivativeFinancialLiabilitiesTable
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1468	Disclosure of maturity analysis for derivative financial liabilities [line items]	LineItems			ifrs-full:DisclosureOfMaturityAnalysisForDerivativeFinancialLiabilitiesLineItems
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1470	1140 - Disclosure - Fair Value - Additional Information (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureFairValueAdditionalInformation
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1476	1141 - Disclosure - Fair Value - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureFairValueAssetsAndLiabilitiesMeasuredAtFairValueOnARecurringBasis
1477	Disclosures of fair value hierarchy of financial assets and financial liabilities [Table]	Table	*	*	hmc:DisclosuresOfFairValueHierarchyOfFinancialAssetsAndFinancialLiabilitiesTable
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1503	1142 - Disclosure - Fair Value - Changes in Level 3 Assets and Liabilities Measured at Fair Value on a Recurring Basis (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureFairValueChangesInLevel3AssetsAndLiabilitiesMeasuredAtFairValueOnARecurringBasis
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1524	1143 - Disclosure - Fair Value - Carrying Amounts and Fair Values of Financial Assets and Financial Liabilities Measured at Amortized Cost (Detail)	Network	*	*	http://imetrix.edgar-online.com/taxonomy/role/DisclosureFairValueCarryingAmountsAndFairValuesOfFinancialAssetsAndFinancialLiabilitiesMeasuredAtAmortizedCost
1525	Disclosures of fair value hierarchy of financial assets and financial liabilities [Table]	Table	*	*	hmc:DisclosuresOfFairValueHierarchyOfFinancialAssetsAndFinancialLiabilitiesTable
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1537	Disclosure of detailed information about financial instruments [table]	Table	*	*	ifrs-full:DisclosureOfFinancialInstrumentsTable
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1564	Future minimum lease payments under non-cancelable operating leases	Concept (Monetary)	As Of	Credit	ifrs-full:MinimumLeasePaymentsPayableUnderNoncancellableOperatingLease
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1610	Honda R&D Co., Ltd. [member]	Member			hmc:HondaRAndDCoLtdMember
1611	Honda Finance Co., Ltd. [member]	Member			hmc:HondaFinanceCoLtdMember
1612	American Honda Motor Co., Inc. [member]	Member			hmc:AmericanHondaMotorCoIncMember
1613	Honda Aero., Inc. [member]	Member			hmc:HondaAeroIncMember
1614	Honda North America, Inc. [member]	Member			hmc:HondaNorthAmericaIncMember
1615	Honda of America Mfg., Inc. [member]	Member			hmc:HondaOfAmericaMfgIncMember
1616	American Honda Finance Corporation [member]	Member			hmc:AmericanHondaFinanceCorporationMember
1617	Honda Aircraft Company, LLC [member]	Member			hmc:HondaAircraftCompanyLLCMember
1618	Honda Manufacturing of Alabama, LLC [member]	Member			hmc:HondaManufacturingOfAlabamaLLCMember
1619	Honda Manufacturing of Indiana, LLC [member]	Member			hmc:HondaManufacturingOfIndianaLLCMember
1620	Honda Transmission Mfg. of America, Inc. [member]	Member			hmc:HondaTransmissionMfgOfAmericaIncMember
1621	Honda R&D Americas, Inc. [member]	Member			hmc:HondaRAndDAmericasIncMember
1622	Honda Canada Inc. [member]	Member			hmc:HondaCanadaIncMember
1623	Honda Canada Finance Inc. [member]	Member			hmc:HondaCanadaFinanceIncMember
1624	Honda de Mexico, S.A. de C.V. [member]	Member			hmc:HondadeMexicoSAdeCVMember
1625	Honda Motor Europe Limited [member]	Member			hmc:HondaMotorEuropeLimitedMember
1626	Honda of the U.K. Manufacturing Ltd. [member]	Member			hmc:HondaOfTheUKManufacturingLtdMember
1627	Honda Finance Europe plc [member]	Member			hmc:HondaFinanceEuropeplcMember
1628	Honda Bank GmbH [member]	Member			hmc:HondaBankGmbHMember
1629	Honda Turkiye A.S [member]	Member			hmc:HondaTurkiyeASMember
1630	Honda Motor (China) Investment Co., Ltd. [member]	Member			hmc:HondaMotorChinaInvestmentCoLtdMember
1631	Honda Auto Parts Manufacturing Co., Ltd. [member]	Member			hmc:HondaAutoPartsManufacturingCoLtdMember
1632	Honda Automobile (China) Co., Ltd. [member]	Member			hmc:HondaAutomobileChinaCoLtdMember
1633	Honda Motorcycle & Scooter India (Private) Ltd. [member]	Member			hmc:HondaMotorcycleAndScooterIndiaPrivateLtdMember
1634	Honda Cars India Limited [member]	Member			hmc:HondaCarsIndiaLimitedMember
1635	P.T. Honda Precision Parts Manufacturing [member]	Member			hmc:PTHondaPrecisionPartsManufacturingMember
1636	P.T. Honda Prospect Motor [member]	Member			hmc:PTHondaProspectMotorMember
1637	Honda Malaysia Sdn Bhd [member]	Member			hmc:HondaMalaysiaSdnBhdMember
1638	Honda Taiwan Co., Ltd. [member]	Member			hmc:HondaTaiwanCoLtdMember
1639	Asian Honda Motor Co., Ltd. [member]	Member			hmc:AsianHondaMotorCoLtdMember
1640	Honda Leasing (Thailand) Co., Ltd. [member]	Member			hmc:HondaLeasingThailandCoLtdMember
1641	Honda Automobile (Thailand) Co., Ltd. [member]	Member			hmc:HondaAutomobileThailandCoLtdMember
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1643	A.P. Honda Co., Ltd. [member]	Member			hmc:APHondaCoLtdMemberMember
1644	Honda Vietnam Co., Ltd. [member]	Member			hmc:HondaVietnamCoLtdMember
1645	Honda Motor de Argentina S.A. [member]	Member			hmc:HondaMotordeArgentinaSAMember
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1647	Banco Honda S.A. [member]	Member			hmc:BancoHondaSAMember
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