Severance, acquisition and other costs (Details) - CAD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Analysis of income and expense [abstract]
Severance	$ (14)	$ 4	$ (245)	$ (230)
Acquisition and other	(27)	(26)	(43)	(21)
Total severance, acquisition and other costs	$ (41)	$ (22)	$ (288)	$ (251)

Acquisition-related costs recognised as expense for transaction recognised separately from acquisition of assets and assumption of liabilities in business combination and other costs

No definition available.

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