Debt due within one year - Details of Securitized Trade Receivables (Details) - CAD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Financial Instruments [Abstract]
Average interest rate throughout the year	1.58%	2.79%
Securitized trade receivables	$ 2,007	$ 2,185

Securitised Trade Receivables, Average Interest Rate During Period

No definition available.

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