Consolidated statements of comprehensive income (Parenthetical) - CAD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Items that will be subsequently reclassified to net earnings
Income tax relating to financial assets measured at fair value through other comprehensive income included in other comprehensive income	$ 0	$ 0
Income tax relating to cash flow hedges	(23)	12
Items that will not be reclassified to net earnings
Income tax relating to actuarial losses on post-employment benefit plans	(653)	(184)
Income tax relating to cash flow hedges	$ (1)	$ 0

Income Tax Relating To Other Comprehensive Income Cash Flow Hedges Not To Be Reclassified To Net Profit Or Loss

No definition available.

Name:	bce_IncomeTaxRelatingToOtherComprehensiveIncomeCashFlowHedgesNotToBeReclassifiedToNetProfitOrLoss
Namespace Prefix:	bce_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The amount of income tax relating to amounts recognised in other comprehensive income in relation to cash flow hedges. [Refer: Cash flow hedges [member]; Other comprehensive income]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 12
-IssueDate 2021-01-01
-Paragraph 81
-Subparagraph ab
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=12&code=ifrs-tx-2021-en-r&anchor=para_81_ab&doctype=Standard
-URIDate 2021-03-24

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2021-01-01
-Paragraph 90
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2021-en-r&anchor=para_90&doctype=Standard
-URIDate 2021-03-24

+ Details

Name:	ifrs-full_IncomeTaxRelatingToCashFlowHedgesOfOtherComprehensiveIncome
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- References

No definition available.

+ Details

Name:	ifrs-full_IncomeTaxRelatingToComponentsOfOtherComprehensiveIncomeThatWillBeReclassifiedToProfitOrLossAbstract
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.

+ Details

Name:	ifrs-full_IncomeTaxRelatingToComponentsOfOtherComprehensiveIncomeThatWillNotBeReclassifiedToProfitOrLossAbstract
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount of income tax relating to amounts recognised in other comprehensive income in relation to financial assets measured at fair value through other comprehensive income applying paragraph 4.1.2A of IFRS 9. [Refer: Financial assets measured at fair value through other comprehensive income; Other comprehensive income]

+ References

+ Details

Name:	ifrs-full_IncomeTaxRelatingToFinancialAssetsMeasuredAtFairValueThroughOtherComprehensiveIncome
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The amount of income tax relating to amounts recognised in other comprehensive income in relation to remeasurements of defined benefit plans. [Refer: Other comprehensive income; Reserve of remeasurements of defined benefit plans; Defined benefit plans [member]]

+ References

+ Details

Name:	ifrs-full_IncomeTaxRelatingToRemeasurementsOfDefinedBenefitPlansOfOtherComprehensiveIncome
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration