Discontinued operations (Details) - CAD ($) $ in Millions		3 Months Ended
Jun. 01, 2020	Dec. 31, 2020
Disclosure of analysis of single amount of discontinued operations [abstract]
Proceeds from sale of operations	$ 1,040	$ 933
Gain recognised on disposal of assets or disposal groups constituting discontinued operation		$ 211

The cash inflow from the disposal of non-current assets or disposal groups classified as held for sale and discontinued operations. [Refer: Discontinued operations [member]; Disposal groups classified as held for sale [member]; Non-current assets or disposal groups classified as held for sale]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 7
-IssueDate 2021-01-01
-Paragraph 16
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=7&code=ifrs-tx-2021-en-r&anchor=para_16&doctype=Standard
-URIDate 2021-03-24

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