Debt due within one year - Details of Securitized Trade Receivables (Details) - CAD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Financial Instruments [Abstract]
Average interest rate throughout the year	1.07%	1.58%
Securitized trade receivables	$ 1,701	$ 2,007

Securitised Trade Receivables, Average Interest Rate During Period

No definition available.

Name:	bce_SecuritisedTradeReceivablesAverageInterestRateDuringPeriod
Namespace Prefix:	bce_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant