Decommissioning Liabilities - Additional Information (Detail) $ in Millions	6 Months Ended	12 Months Ended
Jun. 30, 2022 CAD ($)	Dec. 31, 2021 CAD ($)
Provision for decommissioning, restoration and rehabilitation costs [abstract]
Credit-adjusted risk-free rate	6.20%	4.40%
Restricted Cash	$ 213	$ 186
Inflation rate	0.02	0.02

The amount of non-current restricted cash and cash equivalents. [Refer: Restricted cash and cash equivalents]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2021-01-01
-Paragraph 55
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2021-en-r&anchor=para_55&doctype=Standard
-URIDate 2021-03-24

Name:	ifrs-full_NoncurrentRestrictedCashAndCashEquivalents
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant