VIDEOTRON LTEE (SEC Filing Page | XBRL Cloud Viewer | XBRL Instance)

Line	Label	Object Class	Period Type	Balance	Report ElementName
1	00090 - Document - Document and Entity Information	Network	*	*	http://www.videotron.com/role/DocumentDocumentAndEntityInformation
2	Implied Table	Table	*	*	implied:Table
3	Document and Entity Information [Abstract]	Abstract			vi:DocumentAndEntityInformationAbstract
4	Entity Registrant Name	Concept (Text/String)	For Period		dei:EntityRegistrantName
5	Entity Central Index Key	Concept (CIK Number)	For Period		dei:EntityCentralIndexKey
6	Document Type	Concept (Submission Type)	For Period		dei:DocumentType
7	Document Period End Date	Concept (Date)	For Period		dei:DocumentPeriodEndDate
8	Amendment Flag	Concept (Yes/No)	For Period		dei:AmendmentFlag
9	Current Fiscal Year End Date	Concept (Month/Day)	For Period		dei:CurrentFiscalYearEndDate
10	Entity Well-known Seasoned Issuer	Concept (Yes/No)	For Period		dei:EntityWellKnownSeasonedIssuer
11	Entity Voluntary Filers	Concept (Yes/No)	For Period		dei:EntityVoluntaryFilers
12	Entity Current Reporting Status	Concept (Yes/No)	For Period		dei:EntityCurrentReportingStatus
13	Entity Filer Category	Concept (Filer Category)	For Period		dei:EntityFilerCategory
14	Entity Emerging Growth Company	Concept (Yes/No)	For Period		dei:EntityEmergingGrowthCompany
15	Entity Shell Company	Concept (Yes/No)	For Period		dei:EntityShellCompany
16	Entity Common Stock, Shares Outstanding	Concept (Shares)	As Of		dei:EntityCommonStockSharesOutstanding
17	Document Fiscal Year Focus	Concept (Year)	For Period		dei:DocumentFiscalYearFocus
18	Document Fiscal Period Focus	Concept (Fiscal Period)	For Period		dei:DocumentFiscalPeriodFocus
19	00100 - Statement - CONSOLIDATED STATEMENTS OF INCOME	Network	*	*	http://www.videotron.com/role/StatementConsolidatedStatementsOfIncome
20	Implied Table	Table	*	*	implied:Table
21	CONSOLIDATED STATEMENTS OF INCOME	Abstract			ifrs-full:IncomeStatementAbstract
22	Revenues	Abstract			ifrs-full:RevenueAbstract
23	Cable television	Concept (Monetary)	For Period	Credit	vi:RevenueFromRenderingOfCableTelevisionServices
24	Internet	Concept (Monetary)	For Period	Credit	ifrs-full:RevenueFromRenderingOfInternetServices
25	Mobile telephony	Concept (Monetary)	For Period	Credit	ifrs-full:RevenueFromRenderingOfMobileTelephoneServices
26	Cable telephony	Concept (Monetary)	For Period	Credit	ifrs-full:RevenueFromRenderingOfLandLineTelephoneServices
27	Over-the-top video	Concept (Monetary)	For Period	Credit	vi:RevenueFromRenderingOfOverTopVideoServices
28	Business	Concept (Monetary)	For Period	Credit	vi:RevenueFromRenderingOfBusinessSolutions
29	Equipment sales	Concept (Monetary)	For Period	Credit	ifrs-full:RevenueFromSaleOfTelecommunicationEquipment
30	Other	Concept (Monetary)	For Period	Credit	ifrs-full:RevenueFromRenderingOfOtherTelecommunicationServices
31	Revenues	Concept (Monetary)	For Period	Credit	ifrs-full:RevenueFromContractsWithCustomers
32	Employee costs	Concept (Monetary)	For Period	Debit	ifrs-full:EmployeeBenefitsExpense
33	Purchase of goods and services	Concept (Monetary)	For Period	Debit	ifrs-full:CostOfSales
34	Amortization	Concept (Monetary)	For Period	Debit	ifrs-full:AmortisationExpense
35	Financial expenses	Concept (Monetary)	For Period	Debit	ifrs-full:FinanceCosts
36	Loss on valuation and translation of financial instruments	Concept (Monetary)	For Period	Credit	vi:GainLossOnValuationAndTranslationOfFinancialInstruments
37	Restructuring of operations, litigation and other items	Concept (Monetary)	For Period	Credit	vi:IncomeExpenseFromRestructuringLitigationAndOtherItems
38	Gain on sale of spectrum licences	Concept (Monetary)	For Period	Credit	vi:GainLossOnSaleOfIntangibleAssetsWithIndefiniteUsefulLives
39	Loss on debt refinancing	Concept (Monetary)	For Period	Credit	vi:GainLossOnDebtRefinancing
40	Income before income taxes	Concept (Monetary)	For Period	Credit	ifrs-full:ProfitLossBeforeTax
41	Income taxes (recovery)	Abstract			ifrs-full:MajorComponentsOfTaxExpenseIncomeAbstract
42	Current	Concept (Monetary)	For Period	Debit	ifrs-full:CurrentTaxExpenseIncome
43	Deferred	Concept (Monetary)	For Period	Debit	ifrs-full:DeferredTaxExpenseIncome
44	Income taxes	Concept (Monetary)	For Period	Debit	ifrs-full:IncomeTaxExpenseContinuingOperations
45	Income from continuing operations	Concept (Monetary)	For Period	Credit	ifrs-full:ProfitLossFromContinuingOperations
46	Income from discontinued operations	Concept (Monetary)	For Period	Credit	ifrs-full:ProfitLossFromDiscontinuedOperations
47	Net income	Concept (Monetary)	For Period	Credit	ifrs-full:ProfitLoss
48	Net income from continuing operations attributable to	Abstract			vi:ProfitLossFromContinuingOperationsAttributableToAbstract
49	Shareholders	Concept (Monetary)	For Period	Credit	ifrs-full:IncomeFromContinuingOperationsAttributableToOwnersOfParent
50	Non-controlling interests	Concept (Monetary)	For Period	Credit	ifrs-full:ProfitLossFromContinuingOperationsAttributableToNoncontrollingInterests
51	Net income attributable to	Abstract			ifrs-full:ProfitLossAttributableToAbstract
52	Shareholders	Concept (Monetary)	For Period	Credit	ifrs-full:ProfitLossAttributableToOwnersOfParent
53	Non-controlling interests	Concept (Monetary)	For Period	Credit	ifrs-full:ProfitLossAttributableToNoncontrollingInterests
54	00200 - Statement - CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME	Network	*	*	http://www.videotron.com/role/StatementConsolidatedStatementsOfComprehensiveIncome
55	Implied Table	Table	*	*	implied:Table
56	CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME	Abstract			ifrs-full:StatementOfComprehensiveIncomeAbstract
57	Net income	Concept (Monetary)	For Period	Credit	ifrs-full:ProfitLoss
58	Other comprehensive (loss) income :	Abstract			ifrs-full:OtherComprehensiveIncomeAbstract
59	Items that may be reclassified to income:	Abstract			ifrs-full:ComponentsOfOtherComprehensiveIncomeThatWillBeReclassifiedToProfitOrLossNetOfTaxAbstract
60	Cash flows hedges:	Abstract			ifrs-full:CashFlowHedgesAbstract
61	(Loss) gain on valuation of derivative financial instruments	Concept (Monetary)	For Period	Credit	ifrs-full:GainsLossesOnCashFlowHedgesBeforeTax
62	Deferred income taxes	Concept (Monetary)	For Period	Debit	ifrs-full:IncomeTaxRelatingToCashFlowHedgesOfOtherComprehensiveIncome
63	Items that will not be reclassified to income:	Abstract			ifrs-full:ComponentsOfOtherComprehensiveIncomeThatWillNotBeReclassifiedToProfitOrLossNetOfTaxAbstract
64	Defined benefit plans:	Abstract			vi:DefinedBenefitPlansAbstract
65	Re-measurement (loss) gain	Concept (Monetary)	For Period	Credit	ifrs-full:OtherComprehensiveIncomeBeforeTaxGainsLossesOnRemeasurementsOfDefinedBenefitPlans
66	Deferred income taxes	Concept (Monetary)	For Period	Debit	ifrs-full:IncomeTaxRelatingToRemeasurementsOfDefinedBenefitPlansOfOtherComprehensiveIncome
67	Other comprehensive income (loss)	Concept (Monetary)	For Period	Credit	ifrs-full:OtherComprehensiveIncome
68	Comprehensive income	Concept (Monetary)	For Period	Credit	ifrs-full:ComprehensiveIncome
69	Comprehensive income attributable to	Abstract			ifrs-full:ComprehensiveIncomeAttributableToAbstract
70	Shareholders	Concept (Monetary)	For Period	Credit	ifrs-full:ComprehensiveIncomeAttributableToOwnersOfParent
71	Non-controlling interests	Concept (Monetary)	For Period	Credit	ifrs-full:ComprehensiveIncomeAttributableToNoncontrollingInterests
72	00300 - Statement - CONSOLIDATED STATEMENTS OF EQUITY	Network	*	*	http://www.videotron.com/role/StatementConsolidatedStatementsOfEquity
73	Statement of changes in equity [table]	Table	*	*	ifrs-full:StatementOfChangesInEquityTable
74	Components of equity [axis]	Axis			ifrs-full:ComponentsOfEquityAxis
75	Equity [member]	Member			ifrs-full:EquityMember
76	Equity attributable to shareholders	Member			ifrs-full:EquityAttributableToOwnersOfParentMember
77	Capital stock	Member			ifrs-full:IssuedCapitalMember
78	Retained earnings (deficit)	Member			ifrs-full:RetainedEarningsMember
79	Accumulated other comprehensive loss	Member			ifrs-full:AccumulatedOtherComprehensiveIncomeMember
80	Equity attributable to non-controlling interests	Member			ifrs-full:NoncontrollingInterestsMember
81	Retrospective application and retrospective restatement [axis]	Axis			ifrs-full:RetrospectiveApplicationAndRetrospectiveRestatementAxis
82	Currently stated [member]	Member			ifrs-full:RestatedMember
83	Previously reported	Member			ifrs-full:PreviouslyStatedMember
84	Increase (decrease) due to changes in accounting policy and corrections of prior period errors [member]	Member			ifrs-full:IncreaseDecreaseDueToChangesInAccountingPolicyAndCorrectionsOfPriorPeriodErrorsMember
85	Increase (decrease) due to changes in accounting policy [member]	Member			ifrs-full:FinancialEffectOfChangesInAccountingPolicyMember
86	Increase (decrease) due to changes in accounting policy required by IFRSs [member]	Member			ifrs-full:IncreaseDecreaseDueToChangesInAccountingPolicyRequiredByIFRSsMember
87	Increase (decrease) due to application of IFRS 15	Member			ifrs-full:IncreaseDecreaseDueToApplicationOfIFRS15Member
88	CONSOLIDATED STATEMENTS OF EQUITY	LineItems			ifrs-full:StatementOfChangesInEquityLineItems
89	Equity at beginning of period	Concept (Monetary)	As Of	Credit	ifrs-full:Equity
90	Net income	Concept (Monetary)	For Period	Credit	ifrs-full:ProfitLoss
91	Other comprehensive income (loss)	Concept (Monetary)	For Period	Credit	ifrs-full:OtherComprehensiveIncome
92	Corporate reorganization	Concept (Monetary)	For Period	Credit	vi:CorporateReorganization
93	Reduction of paid-up capital	Concept (Monetary)	For Period	Debit	ifrs-full:ReductionOfIssuedCapital
94	Dividends	Concept (Monetary)	For Period	Debit	ifrs-full:DividendsPaid
95	Equity at end of period	Concept (Monetary)	As Of	Credit	ifrs-full:Equity
96	00400 - Statement - CONSOLIDATED STATEMENTS OF CASH FLOWS	Network	*	*	http://www.videotron.com/role/StatementConsolidatedStatementsOfCashFlows
97	Implied Table	Table	*	*	implied:Table
98	CONSOLIDATED STATEMENTS OF CASH FLOWS	Abstract			ifrs-full:StatementOfCashFlowsAbstract
99	Cash flows related to operating activities	Abstract			ifrs-full:CashFlowsFromUsedInOperatingActivitiesAbstract
100	Income from continuing operations	Concept (Monetary)	For Period	Credit	ifrs-full:ProfitLossFromContinuingOperations
101	Adjustments for:	Abstract			ifrs-full:AdjustmentsForReconcileProfitLossAbstract
102	Amortization of fixed assets	Concept (Monetary)	For Period	Debit	vi:AdjustmentsForAmortisationOnFixedAssets
103	Amortization of intangible assets	Concept (Monetary)	For Period	Debit	ifrs-full:AdjustmentsForAmortisationExpense
104	Loss on valuation and translation of financial instruments	Concept (Monetary)	For Period	Debit	vi:AdjustmentForValuationAndTranslationOfFinancialInstruments
105	Gain on sale of spectrum licences	Concept (Monetary)	For Period	Credit	vi:GainLossOnSaleOfIntangibleAssetsWithIndefiniteUsefulLives
106	Amortization of financing costs and long-term debt discount	Concept (Monetary)	For Period	Debit	vi:AdjustmentsForAmortizationOfFinancingCostsAndLongTermDebtDiscount
107	Deferred income taxes	Concept (Monetary)	For Period	Debit	ifrs-full:AdjustmentsForDeferredTaxExpense
108	Impairment of assets	Concept (Monetary)	For Period	Debit	ifrs-full:ImpairmentLoss
109	Loss on debt refinancing	Concept (Monetary)	For Period	Debit	vi:AdjustmentForLossOnDebtRefinancing
110	Other	Concept (Monetary)	For Period	Debit	ifrs-full:OtherAdjustmentsToReconcileProfitLoss
111	Cash flows before non-cash balances	Concept (Monetary)	For Period		ifrs-full:CashFlowsFromUsedInOperationsBeforeChangesInWorkingCapital
112	Net change in non-cash balances related to operating activities	Concept (Monetary)	For Period	Credit	ifrs-full:IncreaseDecreaseInWorkingCapital
113	Cash flows provided by continuing operating activities	Concept (Monetary)	For Period	Debit	ifrs-full:CashFlowsFromUsedInOperatingActivitiesContinuingOperations
114	Cash flows related to investing activities	Abstract			ifrs-full:CashFlowsFromUsedInInvestingActivitiesAbstract
115	Additions to fixed assets	Concept (Monetary)	For Period	Credit	ifrs-full:PurchaseOfPropertyPlantAndEquipmentClassifiedAsInvestingActivities
116	Additions to intangible assets	Concept (Monetary)	For Period	Credit	ifrs-full:PurchaseOfIntangibleAssetsClassifiedAsInvestingActivities
117	Business acquisition	Concept (Monetary)	For Period	Debit	vi:CashFlowsUsedInObtainingControlOfSubsidiariesOrOtherBusinessesClassifiedAsInvestingActivitiesAdjustments
118	Business acquisition	Concept (Monetary)	For Period	Credit	ifrs-full:CashFlowsUsedInObtainingControlOfSubsidiariesOrOtherBusinessesClassifiedAsInvestingActivities
119	Redemption (issuance) of loan to the parent corporation	Concept (Monetary)	For Period	Debit	vi:RedemptionOrIssuanceOfLoanFromParentClassifiedAsInvestingActivity
120	(Redemption) acquisition of preferred shares from an affiliated corporation	Concept (Monetary)	For Period	Debit	vi:RedemptionAcquisitionOfPreferredSharesOfAffiliatedCorporationClassifiedAsNonCashInvestingActivities
121	Proceeds from disposals of assets	Concept (Monetary)	For Period	Debit	ifrs-full:ProceedsFromOtherLongtermAssetsClassifiedAsInvestingActivities
122	Cash flows (used in) provided by continuing investing activities	Concept (Monetary)	For Period	Debit	ifrs-full:CashFlowsFromUsedInInvestingActivitiesContinuingOperations
123	Cash flows related to financing activities	Abstract			ifrs-full:CashFlowsFromUsedInFinancingActivitiesAbstract
124	Net change in bank indebtedness	Concept (Monetary)	For Period	Debit	vi:CashInflowOutflowDueToChangeInBankIndebtedness
125	Net changes under bank revolving facility	Concept (Monetary)	For Period	Debit	vi:CashInflowOutflowDueToChangeInRevolvingFacilities
126	Issuance of long-term debt, net of financing fees	Concept (Monetary)	For Period	Debit	ifrs-full:ProceedsFromBorrowingsClassifiedAsFinancingActivities
127	Repayment of long-term debt	Concept (Monetary)	For Period	Credit	ifrs-full:RepaymentsOfBorrowingsClassifiedAsFinancingActivities
128	Settlement of hedging contracts	Concept (Monetary)	For Period	Debit	vi:CashInflowOutflowFromSettlementOfHedgingContracts
129	Dividends	Concept (Monetary)	For Period	Credit	ifrs-full:DividendsPaidClassifiedAsFinancingActivities
130	Reduction of paid-up capital	Concept (Monetary)	For Period	Credit	vi:ReductionOfPaidUpCapital
131	Issuance (repayment) of a loan from the parent corporation	Concept (Monetary)	For Period	Debit	vi:IssuanceOfLoanToParentClassifiedAsFinancingActivities
132	Other	Concept (Monetary)	For Period	Debit	ifrs-full:OtherInflowsOutflowsOfCashClassifiedAsFinancingActivities
133	Cash flows used in continuing financing activities	Concept (Monetary)	For Period	Debit	ifrs-full:CashFlowsFromUsedInFinancingActivitiesContinuingOperations
134	Net change in cash and cash equivalents from continuing operations	Concept (Monetary)	For Period	Debit	vi:IncreaseDecreaseInCashAndCashEquivalentsContinuingOperations
135	Cash flows provided by (used in) discontinued operations	Concept (Monetary)	For Period	Debit	ifrs-full:IncreaseDecreaseInCashAndCashEquivalentsDiscontinuedOperations
136	Cash and cash equivalents at the beginning of the year	Concept (Monetary)	As Of	Debit	ifrs-full:CashAndCashEquivalents
137	Cash and cash equivalents at the end of the year	Concept (Monetary)	As Of	Debit	ifrs-full:CashAndCashEquivalents
138	Changes in non-cash balances related to operating activities	Abstract			vi:ChangesInNonCashBalancesRelatedToOperatingActivitiesAbstract
139	Accounts receivable	Concept (Monetary)	For Period	Debit	ifrs-full:AdjustmentsForDecreaseIncreaseInTradeAccountReceivable
140	Contract assets	Concept (Monetary)	For Period	Debit	vi:AdjustmentsForDecreaseIncreaseInContractAssets
141	Amounts receivable from and payable to affiliated corporations	Concept (Monetary)	For Period	Debit	vi:AdjustmentsForAmountsReceivableFromAndPayableToAffiliatedCorporation
142	Inventories	Concept (Monetary)	For Period	Debit	ifrs-full:AdjustmentsForDecreaseIncreaseInInventories
143	Prepaid expenses	Concept (Monetary)	For Period	Debit	vi:AdjustmentsForIncreaseDecreaseInPrepaidExpenses
144	Accounts payable, accrued charges and provisions	Concept (Monetary)	For Period	Debit	vi:AdjustmentsForIncreaseDecreaseInAccountsPayableAccruedChargesAndProvisions
145	Income taxes	Concept (Monetary)	For Period	Debit	ifrs-full:AdjustmentsForIncomeTaxExpense
146	Stock-based compensation	Concept (Monetary)	For Period	Debit	ifrs-full:AdjustmentsForSharebasedPayments
147	Deferred revenues	Concept (Monetary)	For Period	Debit	ifrs-full:AdjustmentsForIncreaseDecreaseInDeferredIncome
148	Defined benefit plans	Concept (Monetary)	For Period	Debit	vi:AdjustmentsForIncreaseInDefinedBenefitPlans
149	Other	Concept (Monetary)	For Period	Debit	ifrs-full:OtherAdjustmentsForNoncashItems
150	Net change in non-cash balances related to operating activities	Concept (Monetary)	For Period	Credit	ifrs-full:IncreaseDecreaseInWorkingCapital
151	Non-cash investing activities	Abstract			vi:NonCashInvestingActivitiesAbstract
152	Net change in additions to fixed assets and intangible assets financed with accounts payable	Concept (Monetary)	For Period	Debit	vi:IncreaseDecreaseInPropertyPlantAndEquipmentAndIntangibleAssets
153	Interest and taxes reflected as operating activities	Abstract			vi:InterestAndTaxesReflectedAsOperatingActivitiesAbstract
154	Cash interest payments	Concept (Monetary)	For Period	Credit	ifrs-full:InterestPaidClassifiedAsOperatingActivities
155	Cash income tax payments (net of refunds)	Concept (Monetary)	For Period	Credit	ifrs-full:IncomeTaxesPaidRefundClassifiedAsOperatingActivities
156	00401 - Statement - CONSOLIDATED STATEMENTS OF CASH FLOWS - Cash information	Network	*	*	http://www.videotron.com/role/StatementConsolidatedStatementsOfCashFlowsCashInformation
157	Implied Table	Table	*	*	implied:Table
158	CONSOLIDATED STATEMENTS OF CASH FLOWS	Abstract			ifrs-full:StatementOfCashFlowsAbstract
159	Cash and cash equivalents consist of	Abstract			ifrs-full:CashAndCashEquivalentsAbstract
160	Cash	Concept (Monetary)	As Of	Debit	ifrs-full:Cash
161	Cash equivalents	Concept (Monetary)	As Of	Debit	ifrs-full:CashEquivalents
162	Total cash and cash equivalents	Concept (Monetary)	As Of	Debit	ifrs-full:CashAndCashEquivalents
163	00500 - Statement - CONSOLIDATED BALANCE SHEETS	Network	*	*	http://www.videotron.com/role/StatementConsolidatedBalanceSheets
164	Implied Table	Table	*	*	implied:Table
165	CONSOLIDATED BALANCE SHEETS	Abstract			ifrs-full:StatementOfFinancialPositionAbstract
166	Assets [abstract]	Abstract			ifrs-full:AssetsAbstract
167	Current assets	Abstract			ifrs-full:CurrentAssetsAbstract
168	Cash and cash equivalents	Concept (Monetary)	As Of	Debit	ifrs-full:CashAndCashEquivalents
169	Accounts receivable	Concept (Monetary)	As Of	Debit	ifrs-full:CurrentTradeReceivables
170	Contract assets	Concept (Monetary)	As Of	Debit	ifrs-full:CurrentContractAssets
171	Amounts receivable from affiliated corporations	Concept (Monetary)	As Of	Debit	ifrs-full:TradeAndOtherCurrentReceivablesDueFromRelatedParties
172	Income taxes	Concept (Monetary)	As Of	Debit	ifrs-full:CurrentTaxAssetsCurrent
173	Inventories	Concept (Monetary)	As Of	Debit	ifrs-full:Inventories
174	Prepaid expenses	Concept (Monetary)	As Of	Debit	ifrs-full:CurrentPrepaidExpenses
175	Other current assets	Concept (Monetary)	As Of	Debit	ifrs-full:OtherCurrentFinancialAssets
176	Assets held for sale	Concept (Monetary)	As Of	Debit	ifrs-full:NoncurrentAssetsOrDisposalGroupsClassifiedAsHeldForSaleOrAsHeldForDistributionToOwners
177	Total current assets	Concept (Monetary)	As Of	Debit	ifrs-full:CurrentAssets
178	Non-current assets	Abstract			ifrs-full:NoncurrentAssetsAbstract
179	Investments	Concept (Monetary)	As Of	Debit	vi:InvestmentsNonCurrent
180	Fixed assets	Concept (Monetary)	As Of	Debit	ifrs-full:PropertyPlantAndEquipment
181	Intangible assets	Concept (Monetary)	As Of	Debit	ifrs-full:IntangibleAssetsOtherThanGoodwill
182	Goodwill	Concept (Monetary)	As Of	Debit	ifrs-full:Goodwill
183	Derivative financial instruments	Concept (Monetary)	As Of	Debit	ifrs-full:DerivativeFinancialAssets
184	Subordinated loan to parent corporation	Concept (Monetary)	As Of	Debit	vi:SubordinatedLoanToParentCorporation
185	Other assets	Concept (Monetary)	As Of	Debit	ifrs-full:OtherNoncurrentFinancialAssets
186	Total non-current assets	Concept (Monetary)	As Of	Debit	ifrs-full:NoncurrentAssets
187	Total assets	Concept (Monetary)	As Of	Debit	ifrs-full:Assets
188	Equity and liabilities [abstract]	Abstract			ifrs-full:EquityAndLiabilitiesAbstract
189	Current liabilities	Abstract			ifrs-full:CurrentLiabilitiesAbstract
190	Bank indebtedness	Concept (Monetary)	As Of	Credit	ifrs-full:ShorttermBorrowings
191	Accounts payable and accrued charges	Concept (Monetary)	As Of	Credit	ifrs-full:TradeAndOtherCurrentPayables
192	Amounts payable to affiliated corporations	Concept (Monetary)	As Of	Credit	ifrs-full:TradeAndOtherCurrentPayablesToRelatedParties
193	Provisions	Concept (Monetary)	As Of	Credit	ifrs-full:CurrentProvisions
194	Deferred revenue	Concept (Monetary)	As Of	Credit	ifrs-full:DeferredIncomeClassifiedAsCurrent
195	Income taxes	Concept (Monetary)	As Of	Credit	ifrs-full:CurrentTaxLiabilitiesCurrent
196	Current portion of long-term debt	Concept (Monetary)	As Of	Credit	ifrs-full:CurrentPortionOfLongtermBorrowings
197	Liabilities held for sale	Concept (Monetary)	As Of	Credit	ifrs-full:LiabilitiesIncludedInDisposalGroupsClassifiedAsHeldForSale
198	Total current liabilities	Concept (Monetary)	As Of	Credit	ifrs-full:CurrentLiabilities
199	Non-current liabilities	Abstract			ifrs-full:NoncurrentLiabilitiesAbstract
200	Long-term debt	Concept (Monetary)	As Of	Credit	ifrs-full:LongtermBorrowings
201	Subordinated loan from parent corporation	Concept (Monetary)	As Of	Credit	vi:SubordinatedLoanFromParentCorporationNonCurrent
202	Derivative financial instruments	Concept (Monetary)	As Of	Credit	ifrs-full:DerivativeFinancialLiabilities
203	Deferred income taxes	Concept (Monetary)	As Of	Credit	ifrs-full:DeferredTaxLiabilities
204	Other liabilities	Concept (Monetary)	As Of	Credit	ifrs-full:OtherNoncurrentFinancialLiabilities
205	Total non-current liabilities	Concept (Monetary)	As Of	Credit	ifrs-full:NoncurrentLiabilities
206	Total liabilities	Concept (Monetary)	As Of	Credit	ifrs-full:Liabilities
207	Equity	Abstract			ifrs-full:EquityAbstract
208	Capital stock	Concept (Monetary)	As Of	Credit	ifrs-full:IssuedCapital
209	(Deficit) retained earnings	Concept (Monetary)	As Of	Credit	ifrs-full:RetainedEarnings
210	Accumulated other comprehensive loss	Concept (Monetary)	As Of	Credit	ifrs-full:AccumulatedOtherComprehensiveIncome
211	Equity attributable to shareholders	Concept (Monetary)	As Of	Credit	ifrs-full:EquityAttributableToOwnersOfParent
212	Non-controlling interests	Concept (Monetary)	As Of	Credit	ifrs-full:NoncontrollingInterests
213	Total equity	Concept (Monetary)	As Of	Credit	ifrs-full:Equity
214	Subsequent events	Concept (Monetary)	As Of	Credit	vi:EventsAfterReportingPeriod
215	Commitments and contingencies	Concept (Monetary)	As Of	Credit	vi:IfrsCommitmentsAndContingencies
216	Guarantees	Concept (Monetary)	As Of	Credit	vi:Guarantees
217	Total liabilities and equity	Concept (Monetary)	As Of	Credit	ifrs-full:EquityAndLiabilities
218	10001 - Disclosure - OTHER EXPLANATORY INFORMATION	Network	*	*	http://www.videotron.com/role/DisclosureOtherExplanatoryInformation
219	Implied Table	Table	*	*	implied:Table
220	OTHER EXPLANATORY INFORMATION	Abstract			vi:DisclosureOfNotesAndOtherExplanatoryInformationAbstract
221	OTHER EXPLANATORY INFORMATION	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfNotesAndOtherExplanatoryInformationExplanatory
222	10101 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	Network	*	*	http://www.videotron.com/role/DisclosureSummaryOfSignificantAccountingPolicies
223	Implied Table	Table	*	*	implied:Table
224	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	Abstract			vi:SummaryOfSignificantAccountingPoliciesAbstract
225	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfSummaryOfSignificantAccountingPoliciesExplanatory
226	10201 - Disclosure - EMPLOYEE COSTS AND PURCHASE OF GOODS AND SERVICES	Network	*	*	http://www.videotron.com/role/DisclosureEmployeeCostsAndPurchaseOfGoodsAndServices
227	Implied Table	Table	*	*	implied:Table
228	EMPLOYEE COSTS AND PURCHASE OF GOODS AND SERVICES	Abstract			vi:EmployeeCostsAndPurchaseOfGoodsAndServicesAbstract
229	EMPLOYEE COSTS AND PURCHASE OF GOODS AND SERVICES	Concept (Text Block (HTML))	For Period		vi:DisclosureOfEmployeeCostsAndPurchaseOfGoodsAndServicesTextBlock
230	10301 - Disclosure - FINANCIAL EXPENSES	Network	*	*	http://www.videotron.com/role/DisclosureFinancialExpenses
231	Implied Table	Table	*	*	implied:Table
232	FINANCIAL EXPENSES	Abstract			vi:FinancialExpensesAbstract
233	FINANCIAL EXPENSES	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfFinanceCostExplanatory
234	10401 - Disclosure - RESTRUCTURING OF OPERATIONS, LITIGATION AND OTHER ITEMS	Network	*	*	http://www.videotron.com/role/DisclosureRestructuringOfOperationsLitigationAndOtherItems
235	Implied Table	Table	*	*	implied:Table
236	RESTRUCTURING OF OPERATIONS, LITIGATION AND OTHER ITEMS	Abstract			vi:RestructuringOfOperationsLitigationAndOtherItemsAbstract
237	RESTRUCTURING OF OPERATIONS, LITIGATION AND OTHER ITEMS	Concept (Text Block (HTML))	For Period		vi:RestructuringOfOperationsLitigationAndOtherItemsTextBlock
238	10501 - Disclosure - GAIN ON SALE OF SPECTRUM LICENCES	Network	*	*	http://www.videotron.com/role/DisclosureGainOnSaleOfSpectrumLicences
239	Implied Table	Table	*	*	implied:Table
240	GAIN ON SALE OF SPECTRUM LICENCES	Abstract			vi:DisclosureOfGainLossOnSaleOfSpectrumLicensesAbstract
241	GAIN ON SALE OF SPECTRUM LICENCES	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfIntangibleAssetsWithIndefiniteUsefulLifeExplanatory
242	10601 - Disclosure - LOSS ON DEBT REFINANCING	Network	*	*	http://www.videotron.com/role/DisclosureLossOnDebtRefinancing
243	Implied Table	Table	*	*	implied:Table
244	LOSS ON DEBT REFINANCING	Abstract			vi:LossOnDebtRefinancingAbstract
245	LOSS ON DEBT REFINANCING	Concept (Text Block (HTML))	For Period		vi:DisclosureOfLossOnDebtRefinancingTextBlock
246	10701 - Disclosure - INCOME TAXES	Network	*	*	http://www.videotron.com/role/DisclosureIncomeTaxes
247	Implied Table	Table	*	*	implied:Table
248	INCOME TAXES	Abstract			ifrs-full:MajorComponentsOfTaxExpenseIncomeAbstract
249	INCOME TAXES	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfIncomeTaxExplanatory
250	10801 - Disclosure - BUSINESS ACQUISITION	Network	*	*	http://www.videotron.com/role/DisclosureBusinessAcquisition
251	Implied Table	Table	*	*	implied:Table
252	BUSINESS ACQUISITION	Abstract			ifrs-full:DisclosureOfBusinessCombinationsAbstract
253	BUSINESS ACQUISITION	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfBusinessCombinationsExplanatory
254	10901 - Disclosure - INVENTORIES	Network	*	*	http://www.videotron.com/role/DisclosureInventories
255	Implied Table	Table	*	*	implied:Table
256	INVENTORIES	Abstract			ifrs-full:ClassesOfInventoriesAbstract
257	INVENTORIES	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfInventoriesExplanatory
258	11001 - Disclosure - SUBORDINATED LOAN TO PARENT CORPORATION	Network	*	*	http://www.videotron.com/role/DisclosureSubordinatedLoanToParentCorporation
259	Implied Table	Table	*	*	implied:Table
260	SUBORDINATED LOAN TO PARENT CORPORATION	Abstract			vi:SubordinatedLoanToParentAbstract
261	SUBORDINATED LOAN TO PARENT CORPORATION	Concept (Text Block (HTML))	For Period		vi:DisclosureOfSubordinatedLoanToParentCorporationTextBlock
262	11101 - Disclosure - INVESTMENTS AND SUBORDINATED LOAN FROM PARENT CORPORATION	Network	*	*	http://www.videotron.com/role/DisclosureInvestmentsAndSubordinatedLoanFromParentCorporation
263	Implied Table	Table	*	*	implied:Table
264	INVESTMENTS AND SUBORDINATED LOAN FROM PARENT CORPORATION	Abstract			vi:InvestmentsAndSubordinatedLoanFromParentCorporationAbstract
265	INVESTMENTS AND SUBORDINATED LOAN FROM PARENT CORPORATION	Concept (Text Block (HTML))	For Period		vi:DisclosureOfInvestmentsAndSubordinatedLoanFromParentCorporationTextBlock
266	11201 - Disclosure - FIXED ASSETS	Network	*	*	http://www.videotron.com/role/DisclosureFixedAssets
267	Implied Table	Table	*	*	implied:Table
268	FIXED ASSETS	Abstract			ifrs-full:PropertyPlantAndEquipmentAbstract
269	FIXED ASSETS	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfPropertyPlantAndEquipmentExplanatory
270	11301 - Disclosure - INTANGIBLE ASSETS	Network	*	*	http://www.videotron.com/role/DisclosureIntangibleAssets
271	Implied Table	Table	*	*	implied:Table
272	INTANGIBLE ASSETS	Abstract			ifrs-full:DisclosureOfIntangibleAssetsAbstract
273	INTANGIBLE ASSETS	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfIntangibleAssetsExplanatory
274	11401 - Disclosure - GOODWILL	Network	*	*	http://www.videotron.com/role/DisclosureGoodwill
275	Implied Table	Table	*	*	implied:Table
276	GOODWILL	Abstract			ifrs-full:DisclosureOfReconciliationOfChangesInGoodwillAbstract
277	GOODWILL	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfGoodwillExplanatory
278	11501 - Disclosure - OTHER ASSETS	Network	*	*	http://www.videotron.com/role/DisclosureOtherAssets
279	Implied Table	Table	*	*	implied:Table
280	OTHER ASSETS	Abstract			ifrs-full:MiscellaneousNoncurrentAssetsAbstract
281	OTHER ASSETS	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfOtherNoncurrentAssetsExplanatory
282	11601 - Disclosure - ACCOUNTS PAYABLE AND ACCRUED CHARGES	Network	*	*	http://www.videotron.com/role/DisclosureAccountsPayableAndAccruedCharges
283	Implied Table	Table	*	*	implied:Table
284	ACCOUNTS PAYABLE AND ACCRUED CHARGES	Abstract			vi:AccountsPayableAndAccruedChargesAbstract
285	ACCOUNTS PAYABLE AND ACCRUED CHARGES	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfTradeAndOtherPayablesExplanatory
286	11701 - Disclosure - PROVISIONS AND CONTINGENCIES	Network	*	*	http://www.videotron.com/role/DisclosureProvisionsAndContingencies
287	Implied Table	Table	*	*	implied:Table
288	PROVISIONS AND CONTINGENCIES	Abstract			vi:DisclosureOfProvisionsAndContingenciesAbstract
289	PROVISIONS AND CONTINGENCIES	Concept (Text Block (HTML))	For Period		vi:DisclosureOfProvisionsAndContingenciesTextBlock
290	11801 - Disclosure - LONG-TERM DEBT	Network	*	*	http://www.videotron.com/role/DisclosureLongTermDebt
291	Implied Table	Table	*	*	implied:Table
292	LONG-TERM DEBT	Abstract			ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsAbstract
293	LONG-TERM DEBT	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfBorrowingsExplanatory
294	11901 - Disclosure - OTHER LIABILITIES	Network	*	*	http://www.videotron.com/role/DisclosureOtherLiabilities
295	Implied Table	Table	*	*	implied:Table
296	OTHER LIABILITIES	Abstract			ifrs-full:MiscellaneousNoncurrentLiabilitiesAbstract
297	OTHER LIABILITIES	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfOtherNoncurrentLiabilitiesExplanatory
298	12001 - Disclosure - CAPITAL STOCK	Network	*	*	http://www.videotron.com/role/DisclosureCapitalStock
299	Implied Table	Table	*	*	implied:Table
300	CAPITAL STOCK	Abstract			ifrs-full:DisclosureOfClassesOfShareCapitalAbstract
301	CAPITAL STOCK	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfShareCapitalReservesAndOtherEquityInterestExplanatory
302	12101 - Disclosure - STOCK-BASED COMPENSATION PLANS	Network	*	*	http://www.videotron.com/role/DisclosureStockBasedCompensationPlans
303	Implied Table	Table	*	*	implied:Table
304	STOCK-BASED COMPENSATION PLANS	Abstract			ifrs-full:DisclosureOfTermsAndConditionsOfSharebasedPaymentArrangementAbstract
305	STOCK-BASED COMPENSATION PLANS	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfSharebasedPaymentArrangementsExplanatory
306	12201 - Disclosure - ACCUMULATED OTHER COMPREHENSIVE LOSS	Network	*	*	http://www.videotron.com/role/DisclosureAccumulatedOtherComprehensiveLoss
307	Implied Table	Table	*	*	implied:Table
308	ACCUMULATED OTHER COMPREHENSIVE LOSS	Abstract			ifrs-full:DisclosureOfAnalysisOfOtherComprehensiveIncomeByItemAbstract
309	ACCUMULATED OTHER COMPREHENSIVE LOSS	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfAnalysisOfOtherComprehensiveIncomeByItemExplanatory
310	12301 - Disclosure - COMMITMENTS	Network	*	*	http://www.videotron.com/role/DisclosureCommitments
311	Implied Table	Table	*	*	implied:Table
312	COMMITMENTS	Abstract			vi:CommitmentsAbstract
313	COMMITMENTS	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfCommitmentsExplanatory
314	12401 - Disclosure - GUARANTEES	Network	*	*	http://www.videotron.com/role/DisclosureGuarantees
315	Implied Table	Table	*	*	implied:Table
316	GUARANTEES	Abstract			vi:DisclosureOfInformationAboutGuaranteesAbstract
317	GUARANTEES	Concept (Text Block (HTML))	For Period		vi:DisclosureOfGuaranteesTextBlock
318	12501 - Disclosure - FINANCIAL INSTRUMENTS AND FINANCIAL RISK MANAGEMENT	Network	*	*	http://www.videotron.com/role/DisclosureFinancialInstrumentsAndFinancialRiskManagement
319	Implied Table	Table	*	*	implied:Table
320	FINANCIAL INSTRUMENTS AND FINANCIAL RISK MANAGEMENT	Abstract			ifrs-full:DisclosureOfFinancialInstrumentsAbstract
321	FINANCIAL INSTRUMENTS AND FINANCIAL RISK MANAGEMENT	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfFinancialInstrumentsExplanatory
322	12601 - Disclosure - RELATED PARTY TRANSACTIONS	Network	*	*	http://www.videotron.com/role/DisclosureRelatedPartyTransactions
323	Implied Table	Table	*	*	implied:Table
324	RELATED PARTY TRANSACTIONS	Abstract			ifrs-full:DisclosureOfTransactionsBetweenRelatedPartiesAbstract
325	RELATED PARTY TRANSACTIONS	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfRelatedPartyExplanatory
326	12701 - Disclosure - PENSION PLANS AND POSTRETIREMENT BENEFITS	Network	*	*	http://www.videotron.com/role/DisclosurePensionPlansAndPostretirementBenefits
327	Implied Table	Table	*	*	implied:Table
328	PENSION PLANS AND POSTRETIREMENT BENEFITS	Abstract			ifrs-full:DisclosureOfDefinedBenefitPlansAbstract
329	PENSION PLANS AND POSTRETIREMENT BENEFITS	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfDefinedBenefitPlansExplanatory
330	12801 - Disclosure - DISCONTINUED OPERATIONS	Network	*	*	http://www.videotron.com/role/DisclosureDiscontinuedOperations
331	Implied Table	Table	*	*	implied:Table
332	DISCONTINUED OPERATIONS	Abstract			ifrs-full:NoncurrentAssetsOrDisposalGroupsClassifiedAsHeldForSaleOrAsHeldForDistributionToOwnersAbstract
333	DISCONTINUED OPERATIONS	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfNoncurrentAssetsHeldForSaleAndDiscontinuedOperationsExplanatory
334	12901 - Disclosure - SUBSEQUENT EVENTS	Network	*	*	http://www.videotron.com/role/DisclosureSubsequentEvents
335	Implied Table	Table	*	*	implied:Table
336	SUBSEQUENT EVENTS	Abstract			ifrs-full:DisclosureOfNonadjustingEventsAfterReportingPeriodAbstract
337	SUBSEQUENT EVENTS	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfEventsAfterReportingPeriodExplanatory
338	20102 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	Network	*	*	http://www.videotron.com/role/DisclosureSummaryOfSignificantAccountingPoliciesPolicies
339	Implied Table	Table	*	*	implied:Table
340	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	Abstract			vi:SummaryOfSignificantAccountingPoliciesAbstract
341	Basis of presentation	Concept (Text Block (HTML))	For Period		vi:DescriptionOfAccountingPolicyForBasisOfPresentationPolicyTextBlock
342	Changes in accounting policies	Concept (Text Block (HTML))	For Period		vi:DescriptionForChangesInAccountingPoliciesPolicyTextBlock
343	Consolidation	Concept (Text Block (HTML))	For Period		ifrs-full:DescriptionOfAccountingPolicyForSubsidiariesExplanatory
344	Business acquisition	Concept (Text Block (HTML))	For Period		ifrs-full:DescriptionOfAccountingPolicyForBusinessCombinationsExplanatory
345	Foreign currency translation	Concept (Text Block (HTML))	For Period		ifrs-full:DescriptionOfAccountingPolicyForForeignCurrencyTranslationExplanatory
346	Revenue recognition	Concept (Text Block (HTML))	For Period		ifrs-full:DescriptionOfAccountingPolicyForRecognitionOfRevenue
347	Impairment of assets	Concept (Text Block (HTML))	For Period		ifrs-full:DescriptionOfAccountingPolicyForImpairmentOfAssetsExplanatory
348	Income taxes	Concept (Text Block (HTML))	For Period		ifrs-full:DescriptionOfAccountingPolicyForIncomeTaxExplanatory
349	Leases	Concept (Text Block (HTML))	For Period		ifrs-full:DescriptionOfAccountingPolicyForLeasesExplanatory
350	Financial instruments	Concept (Text Block (HTML))	For Period		ifrs-full:DescriptionOfAccountingPolicyForFinancialInstrumentsExplanatory
351	Financing fees	Concept (Text Block (HTML))	For Period		ifrs-full:DescriptionOfAccountingPolicyForFinanceCostsExplanatory
352	Tax credits and government assistance	Concept (Text Block (HTML))	For Period		ifrs-full:DescriptionOfAccountingPolicyForGovernmentGrants
353	Cash and cash equivalents	Concept (Text Block (HTML))	For Period		ifrs-full:DescriptionOfAccountingPolicyToDetermineComponentsOfCashAndCashEquivalents
354	Accounts receivable and contract assets	Concept (Text Block (HTML))	For Period		ifrs-full:DescriptionOfAccountingPolicyForTradeAndOtherReceivablesExplanatory
355	Inventories	Concept (Text Block (HTML))	For Period		ifrs-full:DescriptionOfAccountingPolicyForMeasuringInventories
356	Fixed assets	Concept (Text Block (HTML))	For Period		ifrs-full:DescriptionOfAccountingPolicyForPropertyPlantAndEquipmentExplanatory
357	Goodwill and intangible assets	Concept (Text Block (HTML))	For Period		ifrs-full:DescriptionOfAccountingPolicyForIntangibleAssetsAndGoodwillExplanatory
358	Contract costs	Concept (Text Block (HTML))	For Period		vi:DescriptionOfAccountingPolicyForContractCostsPolicyTextBlock
359	Provisions	Concept (Text Block (HTML))	For Period		ifrs-full:DescriptionOfAccountingPolicyForProvisionsExplanatory
360	Stock-based compensation	Concept (Text Block (HTML))	For Period		ifrs-full:DescriptionOfAccountingPolicyForSharebasedPaymentTransactionsExplanatory
361	Pension plans and postretirement benefits	Concept (Text Block (HTML))	For Period		ifrs-full:DescriptionOfAccountingPolicyForEmployeeBenefitsExplanatory
362	Use of estimates and judgments	Concept (Text Block (HTML))	For Period		vi:DescriptionOfAccountingPolicyForUseOfEstimatesAndJudgmentsPolicyTextBlock
363	Recent accounting pronouncements	Concept (Text Block (HTML))	For Period		vi:DescriptionOfAccountingPolicyForRecentAccountingPronouncementsPolicyTextBlock
364	30001 - Disclosure - OTHER EXPLANATORY INFORMATION (Tables)	Network	*	*	http://www.videotron.com/role/DisclosureOtherExplanatoryInformationTables
365	Implied Table	Table	*	*	implied:Table
366	OTHER EXPLANATORY INFORMATION	Abstract			vi:DisclosureOfNotesAndOtherExplanatoryInformationAbstract
367	Schedule of major subsidiaries	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfSignificantInvestmentsInSubsidiariesExplanatory
368	30103 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Tables)	Network	*	*	http://www.videotron.com/role/DisclosureSummaryOfSignificantAccountingPoliciesTables
369	Implied Table	Table	*	*	implied:Table
370	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	Abstract			vi:SummaryOfSignificantAccountingPoliciesAbstract
371	Summary of retroactive adoption of IFRS 15	Concept (Text Block (HTML))	For Period		vi:ExplanationOfRetroactiveAdoptionOfIfrs15TableTextBlock
372	Schedule of fixed assets useful lives	Concept (Text Block (HTML))	For Period		vi:DisclosureOfUsefulLifeOfPropertyPlantAndEquipmentTableTextBlock
373	Schedule of useful lives of intangible assets using the straight-line method	Concept (Text Block (HTML))	For Period		vi:DisclosureOfUsefulLifeOfIntangibleAssetsTableTextBlock
374	Summary of retroactive adoption of IFRS 16	Concept (Text Block (HTML))	For Period		vi:ExplanationOfRetroactiveAdoptionOfIfrs16TableTextBlock
375	30203 - Disclosure - EMPLOYEE COSTS AND PURCHASE OF GOODS AND SERVICES (Tables)	Network	*	*	http://www.videotron.com/role/DisclosureEmployeeCostsAndPurchaseOfGoodsAndServicesTables
376	Implied Table	Table	*	*	implied:Table
377	EMPLOYEE COSTS AND PURCHASE OF GOODS AND SERVICES	Abstract			vi:EmployeeCostsAndPurchaseOfGoodsAndServicesAbstract
378	Schedule of employee costs and purchase of goods and services	Concept (Text Block (HTML))	For Period		vi:DisclosureOfEmployeeCostsAndPurchaseOfGoodsAndServicesTableTextBlock
379	30303 - Disclosure - FINANCIAL EXPENSES (Tables)	Network	*	*	http://www.videotron.com/role/DisclosureFinancialExpensesTables
380	Implied Table	Table	*	*	implied:Table
381	FINANCIAL EXPENSES	Abstract			vi:FinancialExpensesAbstract
382	Schedule of financial expenses	Concept (Text Block (HTML))	For Period		vi:DisclosureOfFinancialExpensesTableTextBlock
383	30703 - Disclosure - INCOME TAXES (Tables)	Network	*	*	http://www.videotron.com/role/DisclosureIncomeTaxesTables
384	Implied Table	Table	*	*	implied:Table
385	INCOME TAXES	Abstract			ifrs-full:MajorComponentsOfTaxExpenseIncomeAbstract
386	Schedule of reconciliation of income taxes at Corporation's domestic statutory tax rate	Concept (Text Block (HTML))	For Period		vi:ScheduleOfIncomeTaxReconciliationAtDomesticStatutoryTaxRateTableTextBlock
387	Schedule of net deferred income tax liability and their impact on deferred income tax expense	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfTemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsExplanatory
388	Summary of changes in net deferred income tax liability	Concept (Text Block (HTML))	For Period		vi:DisclosureOfChangesInNetDeferredIncomeTaxLiabilityTableTextBlock
389	30903 - Disclosure - INVENTORIES (Tables)	Network	*	*	http://www.videotron.com/role/DisclosureInventoriesTables
390	Implied Table	Table	*	*	implied:Table
391	INVENTORIES	Abstract			ifrs-full:ClassesOfInventoriesAbstract
392	Schedule of inventories	Concept (Text Block (HTML))	For Period		vi:DisclosureOfInventoriesTableTextBlock
393	31203 - Disclosure - FIXED ASSETS (Tables)	Network	*	*	http://www.videotron.com/role/DisclosureFixedAssetsTables
394	Implied Table	Table	*	*	implied:Table
395	FIXED ASSETS	Abstract			ifrs-full:PropertyPlantAndEquipmentAbstract
396	Schedule of changes in the net carrying amount of fixed assets	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfDetailedInformationAboutPropertyPlantAndEquipmentExplanatory
397	31303 - Disclosure - INTANGIBLE ASSETS (Tables)	Network	*	*	http://www.videotron.com/role/DisclosureIntangibleAssetsTables
398	Implied Table	Table	*	*	implied:Table
399	INTANGIBLE ASSETS	Abstract			ifrs-full:DisclosureOfIntangibleAssetsAbstract
400	Schedule of changes in the net carrying amount of intangible assets	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfDetailedInformationAboutIntangibleAssetsExplanatory
401	31403 - Disclosure - GOODWILL (Tables)	Network	*	*	http://www.videotron.com/role/DisclosureGoodwillTables
402	Implied Table	Table	*	*	implied:Table
403	GOODWILL	Abstract			ifrs-full:DisclosureOfReconciliationOfChangesInGoodwillAbstract
404	Schedule of changes in the net carrying amount of goodwill	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfReconciliationOfChangesInGoodwillExplanatory
405	Schedule of determination of recoverable amounts in the impairment tests performed in significant CGU groups	Concept (Text Block (HTML))	For Period		vi:DisclosureOfRecoverableAmountsExplanatory
406	31503 - Disclosure - OTHER ASSETS (Tables)	Network	*	*	http://www.videotron.com/role/DisclosureOtherAssetsTables
407	Implied Table	Table	*	*	implied:Table
408	OTHER ASSETS	Abstract			ifrs-full:MiscellaneousNoncurrentAssetsAbstract
409	Schedule of other assets	Concept (Text Block (HTML))	For Period		vi:DisclosureOfOtherAssetsNoncurrentExplanatory
410	31603 - Disclosure - ACCOUNTS PAYABLE AND ACCRUED CHARGES (Tables)	Network	*	*	http://www.videotron.com/role/DisclosureAccountsPayableAndAccruedChargesTables
411	Implied Table	Table	*	*	implied:Table
412	ACCOUNTS PAYABLE AND ACCRUED CHARGES	Abstract			vi:AccountsPayableAndAccruedChargesAbstract
413	Schedule of accounts payable and accrued charges	Concept (Text Block (HTML))	For Period		vi:AccountsPayableAndAccruedChargesTableTextBlock
414	31703 - Disclosure - PROVISIONS AND CONTINGENCIES (Table)	Network	*	*	http://www.videotron.com/role/DisclosureProvisionsAndContingenciesTable
415	Implied Table	Table	*	*	implied:Table
416	PROVISIONS AND CONTINGENCIES	Abstract			vi:DisclosureOfProvisionsAndContingenciesAbstract
417	Summary of provisions and contingencies	Concept (Text Block (HTML))	For Period		vi:DisclosureOfDetailedInformationAboutProvisionsExplanatory
418	31803 - Disclosure - LONG-TERM DEBT (Tables)	Network	*	*	http://www.videotron.com/role/DisclosureLongTermDebtTables
419	Implied Table	Table	*	*	implied:Table
420	LONG-TERM DEBT	Abstract			ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsAbstract
421	Schedule of long-term debt	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsExplanatory
422	Schedule of principal repayments of long-term debt	Concept (Text Block (HTML))	For Period		ifrs-full:MaturityAnalysisForNonderivativeFinancialLiabilities
423	31903 - Disclosure - OTHER LIABILITIES (Tables)	Network	*	*	http://www.videotron.com/role/DisclosureOtherLiabilitiesTables
424	Implied Table	Table	*	*	implied:Table
425	OTHER LIABILITIES	Abstract			ifrs-full:MiscellaneousNoncurrentLiabilitiesAbstract
426	Schedule of other liabilities	Concept (Text Block (HTML))	For Period		vi:DisclosureOfOtherLiabilitiesTableTextBlock
427	32003 - Disclosure - CAPITAL STOCK (Tables)	Network	*	*	http://www.videotron.com/role/DisclosureCapitalStockTables
428	Implied Table	Table	*	*	implied:Table
429	CAPITAL STOCK	Abstract			ifrs-full:DisclosureOfClassesOfShareCapitalAbstract
430	Summary of issued and outstanding capital stock	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfClassesOfShareCapitalExplanatory
431	32103 - Disclosure - STOCK-BASED COMPENSATION PLANS (Tables)	Network	*	*	http://www.videotron.com/role/DisclosureStockBasedCompensationPlansTables
432	Disclosure of terms and conditions of share-based payment arrangement [table]	Table	*	*	ifrs-full:DisclosureOfTermsAndConditionsOfSharebasedPaymentArrangementTable
433	Types of share-based payment arrangements [axis]	Axis			ifrs-full:TypesOfSharebasedPaymentArrangementsAxis
434	Share-based payment arrangements [member]	Member			ifrs-full:SharebasedPaymentArrangementsMember
435	Ultimate parent corporation stock option plan	Member			vi:QuebecorPlansMember
436	Parent corporation stock option plan	Member			vi:QuebecorMediaStockOptionPlanMember
437	STOCK-BASED COMPENSATION PLANS	LineItems			ifrs-full:DisclosureOfTermsAndConditionsOfSharebasedPaymentArrangementLineItems
438	Schedule of information on changes to outstanding options	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfNumberAndWeightedAverageExercisePricesOfShareOptionsExplanatory
439	Schedule of weighted-average assumptions used to estimate the fair value of outstanding stock options	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfIndirectMeasurementOfFairValueOfGoodsOrServicesReceivedShareOptionsGrantedDuringPeriodExplanatory
440	32203 - Disclosure - ACCUMULATED OTHER COMPREHENSIVE LOSS (Tables)	Network	*	*	http://www.videotron.com/role/DisclosureAccumulatedOtherComprehensiveLossTables
441	Implied Table	Table	*	*	implied:Table
442	ACCUMULATED OTHER COMPREHENSIVE LOSS	Abstract			ifrs-full:DisclosureOfAnalysisOfOtherComprehensiveIncomeByItemAbstract
443	Schedule of accumulated other comprehensive loss	Concept (Text Block (HTML))	For Period		vi:DisclosureOfAccumulatedOtherComprehensiveIncomeTableTextBlock
444	32303 - Disclosure - COMMITMENTS (Tables)	Network	*	*	http://www.videotron.com/role/DisclosureCommitmentsTables
445	Implied Table	Table	*	*	implied:Table
446	COMMITMENTS	Abstract			vi:CommitmentsAbstract
447	Schedule of minimum payments	Concept (Text Block (HTML))	For Period		vi:DisclosureOfFutureMinimumPaymentsUnderOperatingLeasesAndOtherContractualCommitmentsTableTextBlock
448	32503 - Disclosure - FINANCIAL INSTRUMENTS AND FINANCIAL RISK MANAGEMENT (Tables)	Network	*	*	http://www.videotron.com/role/DisclosureFinancialInstrumentsAndFinancialRiskManagementTables
449	Disclosure of detailed information about financial instruments [table]	Table	*	*	ifrs-full:DisclosureOfFinancialInstrumentsTable
450	Types of risks [axis]	Axis			ifrs-full:TypesOfRisksAxis
451	Risks [member]	Member			ifrs-full:TypesOfRisksMember
452	Foreign currency risk	Member			ifrs-full:CurrencyRiskMember
453	Interest rate risk	Member			ifrs-full:InterestRateRiskMember
454	Disclosure of detailed information about financial instruments	LineItems			ifrs-full:DisclosureOfFinancialInstrumentsLineItems
455	Schedule of derivative financial instruments	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfDerivativeFinancialInstrumentsExplanatory
456	Schedule of carrying value and fair value of long-term debt and derivative financial instruments	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfFairValueOfFinancialAssetsAndFinancialLiabilitiesAndReclassificationExplanatory
457	Schedule of allowance for doubtful accounts	Concept (Text Block (HTML))	For Period		ifrs-full:DisclosureOfAllowanceForCreditLossesExplanatory
458	Schedule of maturities of financial instruments included capital repayment and interest on long-term debt and obligations related to derivative instruments, less estimated future	Concept (Text Block (HTML))	For Period		vi:MaturityAnalysisForDerivativeAndNonDerivativeFinancialLiabilitiesTextBlock
459	Schedule of estimated sensitivity on income and on other comprehensive income, before income tax	Concept (Text Block (HTML))	For Period		ifrs-full:SensitivityAnalysisForEachTypeOfMarketRisk
460	Schedule of capital structure	Concept (Text Block (HTML))	For Period		vi:DisclosureOfCapitalStructureTableTextBlock
461	32603 - Disclosure - RELATED PARTY TRANSACTIONS (Tables)	Network	*	*	http://www.videotron.com/role/DisclosureRelatedPartyTransactionsTables
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692	Network materials	Concept (Monetary)	As Of	Debit	vi:NetworkMaterials
693	Total current inventories	Concept (Monetary)	As Of	Debit	ifrs-full:Inventories
694	Cost of inventories included in purchase of goods and services	Concept (Monetary)	For Period	Debit	ifrs-full:CostOfInventoriesRecognisedAsExpenseDuringPeriod
695	Write-downs of inventories	Concept (Monetary)	For Period		ifrs-full:InventoryWritedown2011
696	41001 - Disclosure - SUBORDINATED LOAN TO PARENT CORPORATION (Details)	Network	*	*	http://www.videotron.com/role/DisclosureSubordinatedLoanToParentCorporationDetails
697	Disclosure of transactions between related parties [table]	Table	*	*	ifrs-full:DisclosureOfTransactionsBetweenRelatedPartiesTable
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702	Related Parties	LineItems			ifrs-full:DisclosureOfTransactionsBetweenRelatedPartiesLineItems
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706	Subordinated loan reimbursed	Concept (Monetary)	For Period	Credit	vi:NotionalAmountLoansReceivableReimbursedRelatedPartyTransactions
707	41101 - Disclosure - INVESTMENTS AND SUBORDINATED LOAN FROM PARENT CORPORATION (Details)	Network	*	*	http://www.videotron.com/role/DisclosureInvestmentsAndSubordinatedLoanFromParentCorporationDetails
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718	Series B Preferred shares	Member			vi:SeriesBPreferenceSharesMember
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723	Payments for redemption of preferred stock in cash	Concept (Monetary)	For Period	Credit	vi:IfrsPaymentsForRepurchaseOfRedeemablePreferredStock
724	Settlement of cumulative unpaid dividends in cash	Concept (Monetary)	For Period	Credit	vi:PaymentsForCumulativeUnpaidDividends
725	Repayment of subordinated loan	Concept (Monetary)	For Period	Credit	ifrs-full:RepaymentsOfSubordinatedLiabilities
726	Subordinated loan granted during the period	Concept (Monetary)	For Period	Debit	ifrs-full:ProceedsFromIssueOfSubordinatedLiabilities
727	Interest rate on subordinated loan (in percentage)	Concept (Percent)	For Period		vi:IfrsSubordinatedBorrowingInterestRate
728	Repayment term intervals of subordinated loan (in months)	Concept (xbrli:durationItemType)	For Period		vi:SubordinatedBorrowingRepaymentTermIntervals
729	Investment in redeemable preferred shares	Concept (Monetary)	For Period	Credit	vi:PaymentsToAcquireRedeemablePreferredShares
730	Redeemable preferred shares acquired (in shares)	Concept (Shares)	For Period		vi:NumberOfRedeemablePreferredSharesAcquired
731	Preferred stock annual dividend rate (in percentage)	Concept (Percent)	For Period		vi:IfrsPreferredStockDividendRatePercentage
732	41201 - Disclosure - FIXED ASSETS (Details)	Network	*	*	http://www.videotron.com/role/DisclosureFixedAssetsDetails
733	Disclosure of detailed information about property, plant and equipment [table]	Table	*	*	ifrs-full:DisclosureOfPropertyPlantAndEquipmentTable
734	Classes of property, plant and equipment [axis]	Axis			ifrs-full:ClassesOfPropertyPlantAndEquipmentAxis
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737	Furniture and equipment	Member			ifrs-full:FixturesAndFittingsMember
738	Receiving, distribution and telecommunication networks	Member			ifrs-full:CommunicationAndNetworkEquipmentMember
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740	Customer equipment	Member			vi:CustomerEquipmentMember
741	Projects under development	Member			vi:ProjectsUnderDevelopmentMember
742	Carrying amount, accumulated depreciation, amortisation and impairment and gross carrying amount [axis]	Axis			ifrs-full:CarryingAmountAccumulatedDepreciationAmortisationAndImpairmentAndGrossCarryingAmountAxis
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744	Cost	Member			ifrs-full:GrossCarryingAmountMember
745	Accumulated depreciation	Member			ifrs-full:AccumulatedDepreciationAndAmortisationMember
746	Disclosure of detailed information about property, plant and equipment [line items]	LineItems			ifrs-full:DisclosureOfPropertyPlantAndEquipmentLineItems
747	Changes in the net carrying amount of fixed assets	Abstract			ifrs-full:ReconciliationOfChangesInPropertyPlantAndEquipmentAbstract
748	Balance at the beginning of period	Concept (Monetary)	As Of	Debit	ifrs-full:PropertyPlantAndEquipment
749	Additions	Concept (Monetary)	For Period	Debit	ifrs-full:AdditionsOtherThanThroughBusinessCombinationsPropertyPlantAndEquipment
750	Net change in additions financed with accounts payable	Concept (Monetary)	For Period	Debit	vi:IncreaseDecreaseThroughNetChangeInAdditionsFinancedWithAccountsPayable
751	Depreciation	Concept (Monetary)	For Period		ifrs-full:DepreciationPropertyPlantAndEquipment
752	Reclassification	Concept (Monetary)	For Period	Debit	ifrs-full:IncreaseDecreaseThroughTransfersPropertyPlantAndEquipment
753	Reclassification assets held for sale	Concept (Monetary)	For Period	Credit	ifrs-full:DecreaseThroughClassifiedAsHeldForSalePropertyPlantAndEquipment
754	Retirement, disposals and other	Concept (Monetary)	For Period	Credit	vi:DisposalsRetirementsAndOtherPropertyPlantAndEquipment
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757	Increase in depreciation	Concept (Monetary)	For Period	Debit	vi:DepreciationPropertyPlantAndEquipmentChangeInUsefulLifeIncreaseDecrease
758	41301 - Disclosure - INTANGIBLE ASSETS (Details)	Network	*	*	http://www.videotron.com/role/DisclosureIntangibleAssetsDetails
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761	Carrying amount [member]	Member			ifrs-full:CarryingAmountMember
762	Cost	Member			ifrs-full:GrossCarryingAmountMember
763	Accumulated depreciation	Member			ifrs-full:AccumulatedDepreciationAndAmortisationMember
764	Classes of intangible assets other than goodwill [axis]	Axis			ifrs-full:ClassesOfIntangibleAssetsOtherThanGoodwillAxis
765	Intangible assets other than goodwill [member]	Member			ifrs-full:IntangibleAssetsOtherThanGoodwillMember
766	Spectrum licences	Member			vi:SpectrumLicencesMember
767	Software, licences and other intangible assets	Member			vi:SoftwareLicencesAndOtherIntangibleAssetsMember
768	Projects under development	Member			ifrs-full:IntangibleAssetsUnderDevelopmentMember
769	Methods of generation [axis]	Axis			ifrs-full:MethodsOfGenerationAxis
770	Methods of generation [member]	Member			ifrs-full:MethodsOfGenerationMember
771	Internally Generated	Member			ifrs-full:InternallyGeneratedMember
772	Disclosure of detailed information about intangible assets [line items]	LineItems			ifrs-full:DisclosureOfIntangibleAssetsLineItems
773	Changes in the net carrying amount of intangible assets	Abstract			ifrs-full:ReconciliationOfChangesInIntangibleAssetsOtherThanGoodwillAbstract
774	Balance at the beginning of the period	Concept (Monetary)	As Of	Debit	ifrs-full:IntangibleAssetsOtherThanGoodwill
775	Additions	Concept (Monetary)	For Period	Debit	ifrs-full:AdditionsOtherThanThroughBusinessCombinationsIntangibleAssetsOtherThanGoodwill
776	Net change in additions financed with accounts payable	Concept (Monetary)	For Period	Debit	vi:IncreaseDecreaseThroughNetChangeInAdditionsFinancedWithAccountsPayableIntangibleAssetsOtherThanGoodwill
777	Amortization	Concept (Monetary)	For Period		ifrs-full:AmortisationIntangibleAssetsOtherThanGoodwill
778	Reclassification held to sale	Concept (Monetary)	For Period	Credit	ifrs-full:DecreaseThroughClassifiedAsHeldForSaleIntangibleAssetsOtherThanGoodwill
779	Reclassification	Concept (Monetary)	For Period	Debit	ifrs-full:IncreaseDecreaseThroughTransfersAndOtherChangesIntangibleAssetsOtherThanGoodwill
780	Retirement, disposals and other	Concept (Monetary)	For Period	Credit	ifrs-full:DisposalsAndRetirementsIntangibleAssetsOtherThanGoodwill
781	Balance at the end of the period	Concept (Monetary)	As Of	Debit	ifrs-full:IntangibleAssetsOtherThanGoodwill
782	41401 - Disclosure - GOODWILL - Changes in the net carrying amount of goodwill - Cost roll forward (Details)	Network	*	*	http://www.videotron.com/role/DisclosureGoodwillChangesInNetCarryingAmountOfGoodwillCostRollForwardDetails
783	Disclosure of reconciliation of changes in intangible assets and goodwill [table]	Table	*	*	ifrs-full:DisclosureOfReconciliationOfChangesInIntangibleAssetsAndGoodwillTable
784	Carrying amount, accumulated depreciation, amortisation and impairment and gross carrying amount [axis]	Axis			ifrs-full:CarryingAmountAccumulatedDepreciationAmortisationAndImpairmentAndGrossCarryingAmountAxis
785	Carrying amount [member]	Member			ifrs-full:CarryingAmountMember
786	Cost	Member			ifrs-full:GrossCarryingAmountMember
787	Disclosure of reconciliation of changes in intangible assets and goodwill [line items]	LineItems			ifrs-full:DisclosureOfReconciliationOfChangesInIntangibleAssetsAndGoodwillLineItems
788	Changes in the net carrying amount of goodwill	Abstract			ifrs-full:ReconciliationOfChangesInGoodwillAbstract
789	Goodwill at beginning of period	Concept (Monetary)	As Of	Debit	ifrs-full:Goodwill
790	Business acquisition	Concept (Monetary)	For Period	Debit	ifrs-full:IncreaseDecreaseThroughTransfersAndOtherChangesGoodwill
791	Reclassification to assets held for sale	Concept (Monetary)	For Period	Credit	ifrs-full:DecreaseThroughClassifiedAsHeldForSaleGoodwill
792	Goodwill at end of period	Concept (Monetary)	As Of	Debit	ifrs-full:Goodwill
793	41402 - Disclosure - GOODWILL - Changes in the net carrying amount of goodwill - Net carrying amount (Details)	Network	*	*	http://www.videotron.com/role/DisclosureGoodwillChangesInNetCarryingAmountOfGoodwillNetCarryingAmountDetails
794	Disclosure of reconciliation of changes in intangible assets and goodwill [table]	Table	*	*	ifrs-full:DisclosureOfReconciliationOfChangesInIntangibleAssetsAndGoodwillTable
795	Carrying amount, accumulated depreciation, amortisation and impairment and gross carrying amount [axis]	Axis			ifrs-full:CarryingAmountAccumulatedDepreciationAmortisationAndImpairmentAndGrossCarryingAmountAxis
796	Carrying amount [member]	Member			ifrs-full:CarryingAmountMember
797	Cost	Member			ifrs-full:GrossCarryingAmountMember
798	Accumulated amortization	Member			ifrs-full:AccumulatedImpairmentMember
799	Goodwill	LineItems			ifrs-full:DisclosureOfReconciliationOfChangesInIntangibleAssetsAndGoodwillLineItems
800	Goodwill	Concept (Monetary)	As Of	Debit	ifrs-full:Goodwill
801	41403 - Disclosure - GOODWILL - Determination of recoverable amounts in the impairment tests performed in significant CGU groups (Details)	Network	*	*	http://www.videotron.com/role/DisclosureGoodwillDeterminationOfRecoverableAmountsInImpairmentTestsPerformedInSignificantCguGroupsDetails
802	Disclosure of information for cash-generating units [table]	Table	*	*	ifrs-full:DisclosureOfInformationForIndividualAssetOrCashgeneratingUnitWithSignificantAmountOfGoodwillOrIntangibleAssetsWithIndefiniteUsefulLivesTable
803	Cash-generating units [axis]	Axis			ifrs-full:IndividualAssetsOrCashgeneratingUnitsWithSignificantAmountOfGoodwillOrIntangibleAssetsWithIndefiniteUsefulLivesAxis
804	Entity's total for cash-generating units [member]	Member			ifrs-full:EntitysTotalForCashgeneratingUnitsMember
805	Cash-generating units [member]	Member			ifrs-full:IndividualAssetsOrCashgeneratingUnitsWithSignificantAmountOfGoodwillOrIntangibleAssetsWithIndefiniteUsefulLivesMember
806	Telecommunications	Member			vi:TelecommunicationsMember
807	Goodwill	LineItems			ifrs-full:DisclosureOfInformationForIndividualAssetOrCashgeneratingUnitWithSignificantAmountOfGoodwillOrIntangibleAssetsWithIndefiniteUsefulLivesLineItems
808	Percentage of pre-tax discount rate (WACC)	Concept (Percent)	As Of		ifrs-full:DescriptionOfDiscountRatesAppliedToCashFlowProjections
809	Perpetual growth rate	Concept (Percent)	As Of		ifrs-full:DescriptionOfGrowthRateUsedToExtrapolateCashFlowProjections
810	41501 - Disclosure - OTHER ASSETS (Details)	Network	*	*	http://www.videotron.com/role/DisclosureOtherAssetsDetails
811	Implied Table	Table	*	*	implied:Table
812	OTHER ASSETS	Abstract			ifrs-full:MiscellaneousNoncurrentAssetsAbstract
813	Contract assets	Concept (Monetary)	As Of	Debit	ifrs-full:ContractAssets
814	Contract costs	Concept (Monetary)	As Of	Debit	ifrs-full:AssetsRecognisedFromCostsToObtainOrFulfilContractsWithCustomers
815	Other	Concept (Monetary)	As Of	Debit	vi:OtherAssetsOther
816	Other assets	Concept (Monetary)	As Of	Debit	ifrs-full:OtherAssets
817	Less current portion of contract assets	Concept (Monetary)	As Of	Debit	ifrs-full:CurrentContractAssets
818	Less current portion of contract costs (included in "Other current assets")	Concept (Monetary)	As Of	Debit	vi:CurrentContractCosts
819	Total other assets	Concept (Monetary)	As Of	Debit	ifrs-full:OtherNoncurrentFinancialAssets
820	Impairment loss on contract assets	Concept (Monetary)	For Period	Debit	vi:ImpairmentLossOnContractAssets
821	Amortization of contract costs	Concept (Monetary)	For Period	Credit	vi:AmortizationOfContractCosts
822	41601 - Disclosure - ACCOUNTS PAYABLE AND ACCRUED CHARGES (Details)	Network	*	*	http://www.videotron.com/role/DisclosureAccountsPayableAndAccruedChargesDetails
823	Implied Table	Table	*	*	implied:Table
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825	Accounts payable and accrued charges	Abstract			ifrs-full:TradeAndOtherCurrentPayablesAbstract
826	Trade and accruals	Concept (Monetary)	As Of	Credit	vi:CurrentTradePayablesAndAccruals
827	Salaries and employee benefits	Concept (Monetary)	As Of	Credit	ifrs-full:CurrentProvisionsForEmployeeBenefits
828	Interest payable	Concept (Monetary)	As Of	Credit	ifrs-full:InterestPayable
829	Stock-based compensation	Concept (Monetary)	As Of	Credit	vi:CurrentLiabilitiesFromShareBasedPaymentTransactions
830	Total accounts payable and accrued charges	Concept (Monetary)	As Of	Credit	ifrs-full:TradeAndOtherCurrentPayables
831	41701 - Disclosure - PROVISIONS AND CONTINGENCIES - Roll forward (Details)	Network	*	*	http://www.videotron.com/role/DisclosureProvisionsAndContingenciesRollForwardDetails
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834	Reconciliation of changes in provisions	Abstract			ifrs-full:ReconciliationOfChangesInOtherProvisionsAbstract
835	Balance at the beginning of the period	Concept (Monetary)	As Of	Credit	ifrs-full:OtherProvisions
836	Recognized in income	Concept (Monetary)	For Period	Debit	vi:RecognizedInIncomeOtherProvisions
837	Payments	Concept (Monetary)	For Period	Debit	ifrs-full:ProvisionUsedOtherProvisions
838	Other	Concept (Monetary)	For Period	Credit	vi:OtherProvisionsOther
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840	41702 - Disclosure - PROVISIONS AND CONTINGENCIES - Current and non-current (Details)	Network	*	*	http://www.videotron.com/role/DisclosureProvisionsAndContingenciesCurrentAndNonCurrentDetails
841	Implied Table	Table	*	*	implied:Table
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843	Total provisions	Abstract			ifrs-full:OtherProvisionsAbstract
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845	Current portion	Concept (Monetary)	As Of	Credit	ifrs-full:CurrentProvisions
846	Non-current portion	Concept (Monetary)	As Of	Credit	ifrs-full:NoncurrentProvisions
847	41801 - Disclosure - LONG-TERM DEBT - Breakdown of long-term debt (Details)	Network	*	*	http://www.videotron.com/role/DisclosureLongTermDebtBreakdownOfLongTermDebtDetails
848	Disclosure of detailed information about borrowings [table]	Table	*	*	ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsTable
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850	Borrowings by name [member]	Member			ifrs-full:BorrowingsByNameMember
851	Bank credit facilities	Member			vi:BankCreditFacilitiesMember
852	Senior Notes	Member			vi:IfrsSeniorNotesMember
853	Long-term debt	LineItems			ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsLineItems
854	Total long-term debt	Concept (Monetary)	As Of	Credit	ifrs-full:Borrowings
855	Change in fair value related to hedged interest rate risk	Concept (Monetary)	As Of	Credit	vi:ChangeInFairValueRelatedToHedgedInterestRateRisk
856	Financing cost, net of amortization	Concept (Monetary)	As Of	Debit	vi:FinancingFeesNetOfAmortization
857	Total adjustments for long-term debt	Concept (Monetary)	As Of	Debit	vi:AdjustmentsForLongTermDebt
858	Total long-term debt, current and non current	Concept (Monetary)	As Of	Credit	vi:LongTermBorrowingsCurrentAndNoncurrent
859	Less current portion	Concept (Monetary)	As Of	Credit	ifrs-full:CurrentPortionOfLongtermBorrowings
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861	41802 - Disclosure - LONG-TERM DEBT - Bank credit facilities (Details)	Network	*	*	http://www.videotron.com/role/DisclosureLongTermDebtBankCreditFacilitiesDetails
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866	Secured revolving credit facility	Member			vi:SecuredRevolvingCreditFacilityMember
867	Export financing facility	Member			vi:ExportFinancingFacilityMember
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872	Assets carrying value	Concept (Monetary)	As Of	Debit	ifrs-full:Assets
873	Drawn credit facility	Concept (Monetary)	As Of	Credit	vi:DrawnBorrowingFacilities
874	41803 - Disclosure - LONG-TERM DEBT - Senior notes (Details)	Network	*	*	http://www.videotron.com/role/DisclosureLongTermDebtSeniorNotesDetails
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878	Senior Notes	Member			vi:IfrsSeniorNotesMember
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880	Senior Note 5.375% June 2024	Member			vi:SeniorNote5.375PercentJune2024Member
881	Senior Note 5.625% June 2025	Member			vi:SeniorNote5.625PercentJune2025Member
882	Senior Note 5.750% January 2026	Member			vi:SeniorNote5.750PercentJanuary2026Member
883	5.125% Senior Notes due 2027	Member			vi:SeniorNotes5.125PercentDue2017To2027Member
884	Senior Note April 2017	Member			vi:SeniorNoteApril2017Member
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892	41804 - Disclosure - LONG-TERM DEBT - Principal repayments of long-term debt (Details)	Network	*	*	http://www.videotron.com/role/DisclosureLongTermDebtPrincipalRepaymentsOfLongTermDebtDetails
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901	41901 - Disclosure - OTHER LIABILITIES (Details)	Network	*	*	http://www.videotron.com/role/DisclosureOtherLiabilitiesDetails
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908	Other	Concept (Monetary)	As Of	Credit	ifrs-full:OtherNoncurrentLiabilities
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911	42001 - Disclosure - CAPITAL STOCK - Authorized capital stock (Details)	Network	*	*	http://www.videotron.com/role/DisclosureCapitalStockAuthorizedCapitalStockDetails
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970	42102 - Disclosure - STOCK-BASED COMPENSATION PLANS - Ultimate parent corporation outstanding options (Details)	Network	*	*	http://www.videotron.com/role/DisclosureStockBasedCompensationPlansUltimateParentCorporationOutstandingOptionsDetails
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1001	42104 - Disclosure - STOCK-BASED COMPENSATION PLANS - Parent corporation outstanding options (Details)	Network	*	*	http://www.videotron.com/role/DisclosureStockBasedCompensationPlansParentCorporationOutstandingOptionsDetails
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1020	42105 - Disclosure - STOCK-BASED COMPENSATION PLANS - Parent corporation exercise price range of options (Details)	Network	*	*	http://www.videotron.com/role/DisclosureStockBasedCompensationPlansParentCorporationExercisePriceRangeOfOptionsDetails
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1032	42106 - Disclosure - STOCK-BASED COMPENSATION PLANS - Deferred share unit and performance share unit plans (Details)	Network	*	*	http://www.videotron.com/role/DisclosureStockBasedCompensationPlansDeferredShareUnitAndPerformanceShareUnitPlansDetails
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1053	42108 - Disclosure - STOCK-BASED COMPENSATION PLANS - Liability and expense (Details)	Network	*	*	http://www.videotron.com/role/DisclosureStockBasedCompensationPlansLiabilityAndExpenseDetails
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1162	Disclosure of reconciliation of changes in loss allowance and explanation of changes in gross carrying amount for financial instruments [table]	Table	*	*	ifrs-full:DisclosureOfReconciliationOfChangesInLossAllowanceAndExplanationOfChangesInGrossCarryingAmountForFinancialInstrumentsTable
1163	Classes of financial instruments [axis]	Axis			ifrs-full:ClassesOfFinancialInstrumentsAxis
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1169	FINANCIAL INSTRUMENTS AND FINANCIAL RISK MANAGEMENT	LineItems			ifrs-full:DisclosureOfReconciliationOfChangesInLossAllowanceAndExplanationOfChangesInGrossCarryingAmountForFinancialInstrumentsLineItems
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1172	Write-off	Concept (Monetary)	For Period	Credit	ifrs-full:DecreaseThroughDerecognitionFinancialAssets
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1174	42507 - Disclosure - FINANCIAL INSTRUMENTS AND FINANCIAL RISK MANAGEMENT - Liquidity risk management (Details)	Network	*	*	http://www.videotron.com/role/DisclosureFinancialInstrumentsAndFinancialRiskManagementLiquidityRiskManagementDetails
1175	Disclosure of maturity analysis for financial assets held for managing liquidity risk [table]	Table	*	*	ifrs-full:DisclosureOfMaturityAnalysisForFinancialAssetsHeldForManagingLiquidityRiskTable
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1178	2019 (Less than one year)	Member			ifrs-full:NotLaterThanOneYearMember
1179	1-3 years	Member			ifrs-full:LaterThanOneYearAndNotLaterThanThreeYearsMember
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1181	2024 and thereafter (5 years or more)	Member			ifrs-full:LaterThanFiveYearsMember
1182	Types of risks [axis]	Axis			ifrs-full:TypesOfRisksAxis
1183	Risks [member]	Member			ifrs-full:TypesOfRisksMember
1184	Liquidity risk management	Member			ifrs-full:LiquidityRiskMember
1185	FINANCIAL INSTRUMENTS AND FINANCIAL RISK MANAGEMENT	LineItems			ifrs-full:DisclosureOfMaturityAnalysisForFinancialAssetsHeldForManagingLiquidityRiskLineItems
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1188	Accounts payable and accrued charges	Concept (Monetary)	As Of	Credit	ifrs-full:TradeAndOtherPayablesUndiscountedCashFlows
1189	Amounts payable to affiliated corporations	Concept (Monetary)	As Of	Credit	vi:AmountsPayableToAffiliatedCorporationsUndiscountedCashFlows
1190	Long-term debt	Concept (Monetary)	As Of	Credit	vi:LongTermDebtUndiscountedCashFlows
1191	Interest payments	Concept (Monetary)	As Of	Credit	vi:InterestPaymentsUndiscountedCashFlows
1192	Derivative instruments	Concept (Monetary)	As Of	Debit	vi:DerivativeFinancialAssetsUndiscountedCashFlows
1193	Total	Concept (Monetary)	As Of	Credit	vi:FinancialLiabilitiesHeldForManagingLiquidityRisk
1194	42508 - Disclosure - FINANCIAL INSTRUMENTS AND FINANCIAL RISK MANAGEMENT - Market risk (Details)	Network	*	*	http://www.videotron.com/role/DisclosureFinancialInstrumentsAndFinancialRiskManagementMarketRiskDetails
1195	Disclosure of risk management strategy related to hedge accounting [table]	Table	*	*	ifrs-full:DisclosureOfRiskManagementStrategyRelatedToHedgeAccountingTable
1196	Types of risks [axis]	Axis			ifrs-full:TypesOfRisksAxis
1197	Risks [member]	Member			ifrs-full:TypesOfRisksMember
1198	Market risk	Member			ifrs-full:MarketRiskMember
1199	Foreign currency risk	Member			ifrs-full:CurrencyRiskMember
1200	Increase of $0.10	Member			vi:CurrencyAppreciationRiskMember
1201	Decrease of $0.10	Member			vi:CurrencyDepreciationRiskMember
1202	Variance of $0.10 in the foreign currency exchange rate	Member			vi:CurrencyVariationMember
1203	Interest rate risk	Member			ifrs-full:InterestRateRiskMember
1204	Increase of 100 basis points	Member			vi:InterestRateAppreciationRiskMember
1205	Decrease of 100 basis points	Member			vi:InterestRateDepreciationRiskMember
1206	FINANCIAL INSTRUMENTS AND FINANCIAL RISK MANAGEMENT	LineItems			ifrs-full:DisclosureOfRiskManagementStrategyRelatedToHedgeAccountingLineItems
1207	Income	Concept (Monetary)	For Period	Credit	ifrs-full:GainLossOnHedgeIneffectivenessRecognisedInProfitOrLoss
1208	Other comprehensive income	Concept (Monetary)	For Period	Credit	ifrs-full:GainLossOnHedgeIneffectivenessRecognisedInOtherComprehensiveIncome
1209	Unhedged purchase of goods and services	Concept (Monetary)	As Of	Credit	vi:UnhedgedPurchaseOfGoodsAndServices
1210	Unhedged acquisitions of tangible and intangible assets	Concept (Monetary)	As Of	Credit	vi:UnhedgedAcquisitionsOfTangibleAndIntangibleAssets
1211	Long-term debt, fixed-rate debt (in percent)	Concept (Percent)	For Period		vi:LongTermBorrowingsFixedRateDebt
1212	Long-term debt, floating-rate debt (in percent)	Concept (Percent)	For Period		vi:LongTermBorrowingsFloatingRateDebt
1213	Estimated sensitivity on interest payments	Concept (Monetary)	As Of	Credit	vi:EstimatedSensitivityOnInterestPayments
1214	42509 - Disclosure - FINANCIAL INSTRUMENTS AND FINANCIAL RISK MANAGEMENT - Capital management (Details)	Network	*	*	http://www.videotron.com/role/DisclosureFinancialInstrumentsAndFinancialRiskManagementCapitalManagementDetails
1215	Implied Table	Table	*	*	implied:Table
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1217	Bank indebtedness	Concept (Monetary)	As Of	Credit	ifrs-full:ShorttermBorrowings
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1220	Cash and cash equivalents	Concept (Monetary)	As Of	Debit	ifrs-full:CashAndCashEquivalents
1221	Net liabilities	Concept (Monetary)	As Of	Debit	ifrs-full:NetAssetsLiabilities
1222	Equity	Concept (Monetary)	As Of	Credit	ifrs-full:Equity
1223	42601 - Disclosure - RELATED PARTY TRANSACTIONS - Compensation of key management personnel (Details)	Network	*	*	http://www.videotron.com/role/DisclosureRelatedPartyTransactionsCompensationOfKeyManagementPersonnelDetails
1224	Implied Table	Table	*	*	implied:Table
1225	RELATED PARTY TRANSACTIONS	Abstract			ifrs-full:DisclosureOfTransactionsBetweenRelatedPartiesAbstract
1226	Salaries and short-term benefits	Concept (Monetary)	For Period	Debit	vi:KeyManagementPersonnelCompensationSalariesAndShorttermEmployeeBenefits
1227	Share-based compensation	Concept (Monetary)	For Period	Debit	ifrs-full:KeyManagementPersonnelCompensationSharebasedPayment
1228	Other long-term benefits	Concept (Monetary)	For Period	Debit	ifrs-full:KeyManagementPersonnelCompensationOtherLongtermBenefits
1229	Total compensation	Concept (Monetary)	For Period	Debit	ifrs-full:KeyManagementPersonnelCompensation
1230	42602 - Disclosure - RELATED PARTY TRANSACTIONS - Operating transactions (Details)	Network	*	*	http://www.videotron.com/role/DisclosureRelatedPartyTransactionsOperatingTransactionsDetails
1231	Disclosure of transactions between related parties [table]	Table	*	*	ifrs-full:DisclosureOfTransactionsBetweenRelatedPartiesTable
1232	Categories of related parties [axis]	Axis			ifrs-full:CategoriesOfRelatedPartiesAxis
1233	Entity's total for related parties [member]	Member			ifrs-full:EntitysTotalForRelatedPartiesMember
1234	Parent	Member			ifrs-full:ParentMember
1235	Corporations under common control	Member			vi:CorporationsUnderCommonControlMember
1236	RELATED PARTY TRANSACTIONS	LineItems			ifrs-full:DisclosureOfTransactionsBetweenRelatedPartiesLineItems
1237	Revenues	Concept (Monetary)	For Period	Credit	vi:RevenueFromSaleOfGoodsAndServicesRelatedPartyTransactions
1238	Purchase of goods and services	Concept (Monetary)	For Period	Debit	vi:PurchasesOfGoodsAndServicesRelatedPartyTransactions
1239	Operating expenses recovered	Concept (Monetary)	For Period	Credit	vi:OperatingExpensesRecoveredRelatedPartyTransactions
1240	42603 - Disclosure - RELATED PARTY TRANSACTIONS - Accounts receivable from affiliated corporations (Details)	Network	*	*	http://www.videotron.com/role/DisclosureRelatedPartyTransactionsAccountsReceivableFromAffiliatedCorporationsDetails
1241	Disclosure of transactions between related parties [table]	Table	*	*	ifrs-full:DisclosureOfTransactionsBetweenRelatedPartiesTable
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1244	Parent	Member			ifrs-full:ParentMember
1245	Corporations under common control	Member			vi:CorporationsUnderCommonControlMember
1246	RELATED PARTY TRANSACTIONS	LineItems			ifrs-full:DisclosureOfTransactionsBetweenRelatedPartiesLineItems
1247	Accounts receivable	Concept (Monetary)	As Of	Debit	vi:AccountsReceivableRelatedPartyTransactions
1248	Interest receivable	Concept (Monetary)	As Of	Debit	vi:InterestReceivableRelatedPartyTransactions
1249	Dividends receivable	Concept (Monetary)	As Of	Debit	vi:RelatedPartyTransactionsDividendsReceivable
1250	Total receivables	Concept (Monetary)	As Of	Debit	ifrs-full:AmountsReceivableRelatedPartyTransactions
1251	42604 - Disclosure - RELATED PARTY TRANSACTIONS - Accounts payable to affiliated corporations (Details)	Network	*	*	http://www.videotron.com/role/DisclosureRelatedPartyTransactionsAccountsPayableToAffiliatedCorporationsDetails
1252	Disclosure of transactions between related parties [table]	Table	*	*	ifrs-full:DisclosureOfTransactionsBetweenRelatedPartiesTable
1253	Categories of related parties [axis]	Axis			ifrs-full:CategoriesOfRelatedPartiesAxis
1254	Entity's total for related parties [member]	Member			ifrs-full:EntitysTotalForRelatedPartiesMember
1255	Parent	Member			ifrs-full:ParentMember
1256	Corporations under common control	Member			vi:CorporationsUnderCommonControlMember
1257	RELATED PARTY TRANSACTIONS	LineItems			ifrs-full:DisclosureOfTransactionsBetweenRelatedPartiesLineItems
1258	Accounts payable	Concept (Monetary)	As Of	Credit	vi:AccountsPayableRelatedPartyTransactions
1259	Interest payable	Concept (Monetary)	As Of	Credit	vi:RelatedPartyTransactionsInterestPayable
1260	Total payables	Concept (Monetary)	As Of	Credit	ifrs-full:AmountsPayableRelatedPartyTransactions
1261	42605 - Disclosure - RELATED PARTY TRANSACTIONS - Management arrangements (Details)	Network	*	*	http://www.videotron.com/role/DisclosureRelatedPartyTransactionsManagementArrangementsDetails
1262	Implied Table	Table	*	*	implied:Table
1263	RELATED PARTY TRANSACTIONS	Abstract			ifrs-full:DisclosureOfTransactionsBetweenRelatedPartiesAbstract
1264	Management fees	Concept (Monetary)	For Period	Debit	ifrs-full:ServicesReceivedRelatedPartyTransactions
1265	42701 - Disclosure - PENSION PLANS AND POSTRETIREMENT BENEFITS - Changes in the plans benefit obligations (Details)	Network	*	*	http://www.videotron.com/role/DisclosurePensionPlansAndPostretirementBenefitsChangesInPlansBenefitObligationsDetails
1266	Disclosure of net defined benefit liability (asset) [table]	Table	*	*	ifrs-full:DisclosureOfNetDefinedBenefitLiabilityAssetTable
1267	Net defined benefit liability (asset) [axis]	Axis			ifrs-full:NetDefinedBenefitLiabilityAssetAxis
1268	Net defined benefit liability (asset) [member]	Member			ifrs-full:NetDefinedBenefitLiabilityAssetMember
1269	Present value of defined benefit	Member			ifrs-full:PresentValueOfDefinedBenefitObligationMember
1270	Characteristics of defined benefit plans [axis]	Axis			ifrs-full:CharacteristicsOfDefinedBenefitPlansAxis
1271	Characteristics of defined benefit plans [member]	Member			ifrs-full:CharacteristicsOfDefinedBenefitPlansMember
1272	Pension defined benefit plans	Member			ifrs-full:PensionDefinedBenefitPlansMember
1273	Postretirement defined benefit plans	Member			vi:PostretirementDefinedBenefitPlansMember
1274	Disclosure of net defined benefit liability (asset)	LineItems			ifrs-full:DisclosureOfNetDefinedBenefitLiabilityAssetLineItems
1275	Benefit obligations at the beginning of the year	Concept (Monetary)	As Of	Credit	ifrs-full:LiabilityAssetOfDefinedBenefitPlans
1276	Service costs	Concept (Monetary)	For Period	Credit	ifrs-full:CurrentServiceCostNetDefinedBenefitLiabilityAsset
1277	Interest costs	Concept (Monetary)	For Period	Credit	ifrs-full:InterestExpenseIncomeNetDefinedBenefitLiabilityAsset
1278	Plan participants' contributions	Concept (Monetary)	For Period	Debit	ifrs-full:ContributionsToPlanByPlanParticipantsNetDefinedBenefitLiabilityAsset
1279	Actuarial (gain) loss arising from:	Abstract			ifrs-full:GainLossOnRemeasurementOfNetDefinedBenefitLiabilityAssetAbstract
1280	Demographic assumptions	Concept (Monetary)	For Period	Debit	ifrs-full:ActuarialGainsLossesArisingFromChangesInDemographicAssumptionsNetDefinedBenefitLiabilityAsset
1281	Financial assumptions	Concept (Monetary)	For Period	Debit	ifrs-full:ActuarialGainsLossesArisingFromChangesInFinancialAssumptionsNetDefinedBenefitLiabilityAsset
1282	Participant experience	Concept (Monetary)	For Period	Debit	vi:ActuarialGainsLossesArisingFromChangesInParticipantExperienceNetDefinedBenefitLiabilityAsset
1283	Benefits and settlements paid	Concept (Monetary)	For Period	Debit	vi:PaymentsAndSettlementsNetDefinedBenefitLiabilityAsset
1284	Other	Concept (Monetary)	For Period	Credit	ifrs-full:IncreaseDecreaseThroughOtherChangesNetDefinedBenefitLiabilityAsset
1285	Benefit obligations at the end of the year	Concept (Monetary)	As Of	Credit	ifrs-full:LiabilityAssetOfDefinedBenefitPlans
1286	42702 - Disclosure - PENSION PLANS AND POSTRETIREMENT BENEFITS - Changes in the fair value of plan assets (Details)	Network	*	*	http://www.videotron.com/role/DisclosurePensionPlansAndPostretirementBenefitsChangesInFairValueOfPlanAssetsDetails
1287	Disclosure of net defined benefit liability (asset) [table]	Table	*	*	ifrs-full:DisclosureOfNetDefinedBenefitLiabilityAssetTable
1288	Net defined benefit liability (asset) [axis]	Axis			ifrs-full:NetDefinedBenefitLiabilityAssetAxis
1289	Net defined benefit liability (asset) [member]	Member			ifrs-full:NetDefinedBenefitLiabilityAssetMember
1290	Plan assets	Member			ifrs-full:PlanAssetsMember
1291	Characteristics of defined benefit plans [axis]	Axis			ifrs-full:CharacteristicsOfDefinedBenefitPlansAxis
1292	Characteristics of defined benefit plans [member]	Member			ifrs-full:CharacteristicsOfDefinedBenefitPlansMember
1293	Pension defined benefit plans	Member			ifrs-full:PensionDefinedBenefitPlansMember
1294	Postretirement defined benefit plans	Member			vi:PostretirementDefinedBenefitPlansMember
1295	Disclosure of net defined benefit liability (asset)	LineItems			ifrs-full:DisclosureOfNetDefinedBenefitLiabilityAssetLineItems
1296	Fair value of plan assets at the beginning of the year	Concept (Monetary)	As Of	Credit	ifrs-full:LiabilityAssetOfDefinedBenefitPlans
1297	Actual return on plan assets	Concept (Monetary)	For Period	Debit	ifrs-full:ReturnOnPlanAssetsNetDefinedBenefitLiabilityAsset
1298	Employer contributions	Concept (Monetary)	For Period	Debit	ifrs-full:ContributionsToPlanByEmployerNetDefinedBenefitLiabilityAsset
1299	Plan participants' contributions	Concept (Monetary)	For Period	Debit	ifrs-full:ContributionsToPlanByPlanParticipantsNetDefinedBenefitLiabilityAsset
1300	Benefits and settlements paid	Concept (Monetary)	For Period	Debit	vi:PaymentsAndSettlementsNetDefinedBenefitLiabilityAsset
1301	Other	Concept (Monetary)	For Period	Credit	ifrs-full:IncreaseDecreaseThroughOtherChangesNetDefinedBenefitLiabilityAsset
1302	Fair value of plan assets at the end of the year	Concept (Monetary)	As Of	Credit	ifrs-full:LiabilityAssetOfDefinedBenefitPlans
1303	42703 - Disclosure - PENSION PLANS AND POSTRETIREMENT BENEFITS - Components of plan assets and reconciliation of funded status (Details)	Network	*	*	http://www.videotron.com/role/DisclosurePensionPlansAndPostretirementBenefitsComponentsOfPlanAssetsAndReconciliationOfFundedStatusDetails
1304	Disclosure of defined benefit plans [table]	Table	*	*	ifrs-full:DisclosureOfDefinedBenefitPlansTable
1305	Net defined benefit liability (asset) [axis]	Axis			ifrs-full:NetDefinedBenefitLiabilityAssetAxis
1306	Net defined benefit liability (asset) [member]	Member			ifrs-full:NetDefinedBenefitLiabilityAssetMember
1307	Plan assets	Member			ifrs-full:PlanAssetsMember
1308	Characteristics of defined benefit plans [axis]	Axis			ifrs-full:CharacteristicsOfDefinedBenefitPlansAxis
1309	Characteristics of defined benefit plans [member]	Member			ifrs-full:CharacteristicsOfDefinedBenefitPlansMember
1310	Pension defined benefit plans	Member			ifrs-full:PensionDefinedBenefitPlansMember
1311	Postretirement defined benefit plans	Member			vi:PostretirementDefinedBenefitPlansMember
1312	Geographical areas [axis]	Axis			ifrs-full:GeographicalAreasAxis
1313	Geographical areas [member]	Member			ifrs-full:GeographicalAreasMember
1314	Canadian	Member			ifrs-full:CountryOfDomicileMember
1315	Foreign	Member			ifrs-full:ForeignCountriesMember
1316	Disclosure of net defined benefit liability (asset)	LineItems			ifrs-full:DisclosureOfDefinedBenefitPlansLineItems
1317	Weighted average duration of defined benefit obligations	Concept (Decimal)	For Period		ifrs-full:WeightedAverageDurationOfDefinedBenefitObligation
1318	Expected future benefit payments	Concept (Monetary)	As Of	Credit	vi:ExpectedFutureBenefitPayments
1319	Plan assets	Abstract			vi:PlanAssetsAbstract
1320	Equity securities (as a percent)	Concept (Percent)	For Period		vi:TotalPlanAssetsEquitySecuritiesPercentage
1321	Debt securities (as a percent)	Concept (Percent)	For Period		vi:TotalPlanAssetsDebtSecuritiesPercentage
1322	Other (as a percent)	Concept (Percent)	For Period		vi:TotalPlanAssetsOtherPercentage
1323	Total plan assets (in percent)	Concept (Percent)	For Period		vi:TotalPlanAssetsPercentage
1324	Reconciliation of funded status to net amount recognized	Abstract			vi:ReconciliationOfFundedStatusToNetAmountRecognizedOfBenefitObligationsAbstract
1325	Benefit obligations	Concept (Monetary)	As Of	Credit	ifrs-full:DefinedBenefitObligationAtPresentValue
1326	Fair value of plan assets	Concept (Monetary)	As Of	Debit	ifrs-full:PlanAssetsAtFairValue
1327	Plan deficit and net amount recognized	Concept (Monetary)	As Of	Debit	vi:NetRecognizedAmountOfDefinedBenefitLiabilityAsset
1328	42704 - Disclosure - PENSION PLANS AND POSTRETIREMENT BENEFITS - Components of re-measurements (Details)	Network	*	*	http://www.videotron.com/role/DisclosurePensionPlansAndPostretirementBenefitsComponentsOfReMeasurementsDetails
1329	Disclosure of fair value of plan assets [table]	Table	*	*	ifrs-full:DisclosureOfFairValueOfPlanAssetsTable
1330	Characteristics of defined benefit plans [axis]	Axis			ifrs-full:CharacteristicsOfDefinedBenefitPlansAxis
1331	Characteristics of defined benefit plans [member]	Member			ifrs-full:CharacteristicsOfDefinedBenefitPlansMember
1332	Pension defined benefit plans	Member			ifrs-full:PensionDefinedBenefitPlansMember
1333	Postretirement defined benefit plans	Member			vi:PostretirementDefinedBenefitPlansMember
1334	Disclosure of net defined benefit liability (asset)	LineItems			ifrs-full:DisclosureOfFairValueOfPlanAssetsLineItems
1335	Actuarial (loss) gain on benefit obligations	Concept (Monetary)	For Period	Credit	vi:ActuarialGainsLossesNetDefinedBenefitLiabilityAsset
1336	Actual return on plan assets, less interest income anticipated in the interest on the net defined benefit liability calculation	Concept (Monetary)	For Period	Credit	vi:ReturnOnPlanAssetsNetOfInterestIncomeNetDefinedBenefitLiabilityAsset
1337	Re-measurements (loss) gain recorded in other comprehensive income	Concept (Monetary)	For Period	Credit	ifrs-full:OtherComprehensiveIncomeNetOfTaxGainsLossesOnRemeasurementsOfDefinedBenefitPlans
1338	42705 - Disclosure - PENSION PLANS AND POSTRETIREMENT BENEFITS - Components of the net benefit costs (Details)	Network	*	*	http://www.videotron.com/role/DisclosurePensionPlansAndPostretirementBenefitsComponentsOfNetBenefitCostsDetails
1339	Disclosure of defined benefit plans [table]	Table	*	*	ifrs-full:DisclosureOfDefinedBenefitPlansTable
1340	Characteristics of defined benefit plans [axis]	Axis			ifrs-full:CharacteristicsOfDefinedBenefitPlansAxis
1341	Characteristics of defined benefit plans [member]	Member			ifrs-full:CharacteristicsOfDefinedBenefitPlansMember
1342	Pension defined benefit plans	Member			ifrs-full:PensionDefinedBenefitPlansMember
1343	Postretirement defined benefit plans	Member			vi:PostretirementDefinedBenefitPlansMember
1344	Disclosure of net defined benefit liability (asset)	LineItems			ifrs-full:DisclosureOfDefinedBenefitPlansLineItems
1345	Employee costs:	Abstract			ifrs-full:ClassesOfEmployeeBenefitsExpenseAbstract
1346	Service costs	Concept (Monetary)	For Period	Debit	vi:DefinedBenefitPlansServiceCost
1347	Administrative fees and other	Concept (Monetary)	For Period	Debit	vi:DefinedBenefitPlansAdministrativeAndOtherExpense
1348	Interest on net defined benefit liability	Concept (Monetary)	For Period	Debit	vi:DefinedBenefitPlansInterestExpense
1349	Net benefit costs	Concept (Monetary)	For Period	Debit	ifrs-full:PostemploymentBenefitExpenseDefinedBenefitPlans
1350	42706 - Disclosure - PENSION PLANS AND POSTRETIREMENT BENEFITS - Defined contribution pension plans (Details)	Network	*	*	http://www.videotron.com/role/DisclosurePensionPlansAndPostretirementBenefitsDefinedContributionPensionPlansDetails
1351	Implied Table	Table	*	*	implied:Table
1352	PENSION PLANS AND POSTRETIREMENT BENEFITS	Abstract			ifrs-full:DisclosureOfDefinedBenefitPlansAbstract
1353	Defined contribution expense	Concept (Monetary)	For Period	Debit	ifrs-full:PostemploymentBenefitExpenseDefinedContributionPlans
1354	42707 - Disclosure - PENSION PLANS AND POSTRETIREMENT BENEFITS - Assumptions and sensitivity analysis (Details)	Network	*	*	http://www.videotron.com/role/DisclosurePensionPlansAndPostretirementBenefitsAssumptionsAndSensitivityAnalysisDetails
1355	Disclosure of defined benefit plans [table]	Table	*	*	ifrs-full:DisclosureOfDefinedBenefitPlansTable
1356	Net defined benefit liability (asset) [axis]	Axis			ifrs-full:NetDefinedBenefitLiabilityAssetAxis
1357	Net defined benefit liability (asset) [member]	Member			ifrs-full:NetDefinedBenefitLiabilityAssetMember
1358	Plan assets	Member			ifrs-full:PlanAssetsMember
1359	Actuarial assumptions [axis]	Axis			ifrs-full:ActuarialAssumptionsAxis
1360	Actuarial assumptions [member]	Member			ifrs-full:ActuarialAssumptionsMember
1361	Actuarial assumption discount rate	Member			ifrs-full:ActuarialAssumptionOfDiscountRatesMember
1362	Characteristics of defined benefit plans [axis]	Axis			ifrs-full:CharacteristicsOfDefinedBenefitPlansAxis
1363	Characteristics of defined benefit plans [member]	Member			ifrs-full:CharacteristicsOfDefinedBenefitPlansMember
1364	Pension defined benefit plans	Member			ifrs-full:PensionDefinedBenefitPlansMember
1365	Postretirement defined benefit plans	Member			vi:PostretirementDefinedBenefitPlansMember
1366	Pension and postretirement benefits	LineItems			ifrs-full:DisclosureOfDefinedBenefitPlansLineItems
1367	Expected employer contributions in the next fiscal year	Concept (Monetary)	For Period	Credit	ifrs-full:EstimateOfContributionsExpectedToBePaidToPlan
1368	Employer contributions	Concept (Monetary)	For Period	Debit	ifrs-full:ContributionsToPlanByEmployerNetDefinedBenefitLiabilityAsset
1369	Benefit obligations	Abstract			ifrs-full:DisclosureOfNetDefinedBenefitLiabilityAssetAbstract
1370	Discount rate, current year (as a percent)	Concept (Percent)	As Of		vi:ActuarialAssumptionOfDiscountRatesCurrentYear
1371	Rate of compensation increase, current year (as a percent)	Concept (Percent)	As Of		vi:ActuarialAssumptionOfExpectedRatesOfCompensationIncreasesCurrentYear
1372	Decrease of retirement benefit obligation due to increase of actuarial assumption	Concept (Monetary)	As Of	Credit	ifrs-full:IncreaseDecreaseInDefinedBenefitObligationDueToReasonablyPossibleIncreaseInActuarialAssumption
1373	Percentage increase of discount rate (as a percent)	Concept (Percent)	As Of		ifrs-full:PercentageOfReasonablyPossibleIncreaseInActuarialAssumption
1374	Current periodic costs	Abstract			vi:CurrentPeriodicCostsAbstract
1375	Discount rate, preceding year (as a percent)	Concept (Percent)	As Of		vi:ActuarialAssumptionOfDiscountRatesPrecedingYear
1376	Rate of compensation increase, preceding year (as a percent)	Concept (Percent)	As Of		vi:ActuarialAssumptionOfExpectedRatesOfCompensationIncreasesPrecedingYear
1377	Assumed average retirement age	Concept (Decimal)	As Of		ifrs-full:ActuarialAssumptionOfRetirementAge
1378	Assumed health care cost trend rate (as a percent)	Concept (Percent)	As Of		ifrs-full:ActuarialAssumptionOfMedicalCostTrendRates
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1405	Income from discontinued operations	Concept (Monetary)	For Period	Credit	ifrs-full:ProfitLossFromDiscontinuedOperations
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1409	Cash flows related to operating activities	Concept (Monetary)	For Period	Debit	ifrs-full:CashFlowsFromUsedInOperatingActivitiesDiscontinuedOperations
1410	Cash flows related to investing activities	Concept (Monetary)	For Period	Debit	ifrs-full:CashFlowsFromUsedInInvestingActivitiesDiscontinuedOperations
1411	Cash flows provided by (used in) discontinued operations	Concept (Monetary)	For Period	Debit	ifrs-full:IncreaseDecreaseInCashAndCashEquivalentsDiscontinuedOperations
1412	42804 - Disclosure - DISCONTINUED OPERATIONS - Discontinued operations statements of consolidated balance sheet (Details)	Network	*	*	http://www.videotron.com/role/DisclosureDiscontinuedOperationsDiscontinuedOperationsStatementsOfConsolidatedBalanceSheetDetails
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1416	Assets and liabilities classified as held for sale	Member			ifrs-full:AssetsAndLiabilitiesClassifiedAsHeldForSaleMember
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1418	Net assets held for sale	Abstract			ifrs-full:NetAssetsLiabilitiesAbstract
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1420	Fixed assets	Concept (Monetary)	As Of	Debit	ifrs-full:PropertyPlantAndEquipment
1421	Goodwill and intangible assets	Concept (Monetary)	As Of	Debit	ifrs-full:IntangibleAssetsAndGoodwill
1422	Assets	Concept (Monetary)	As Of	Debit	ifrs-full:Assets
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1424	Net assets	Concept (Monetary)	As Of	Debit	ifrs-full:NetAssetsLiabilities
1425	42901 - Disclosure - SUBSEQUENT EVENTS (Details)	Network	*	*	http://www.videotron.com/role/DisclosureSubsequentEventsDetails
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1429	Reduction of paid-up capital	Member			vi:ReductionOfPaidUpCapitalMember
1430	Major ordinary share transactions	Member			ifrs-full:MajorOrdinaryShareTransactionsMember
1431	Components of equity [axis]	Axis			ifrs-full:ComponentsOfEquityAxis
1432	Equity [member]	Member			ifrs-full:EquityMember
1433	Capital stock	Member			ifrs-full:IssuedCapitalMember
1434	Categories of related parties [axis]	Axis			ifrs-full:CategoriesOfRelatedPartiesAxis
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1437	SUBSEQUENT EVENTS	LineItems			ifrs-full:DisclosureOfNonadjustingEventsAfterReportingPeriodLineItems
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