Income Taxes - Components of Income Tax Expense (Recovery) Recognized in Other Comprehensive Income ("OCI") (Detail) - CAD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Major components of tax expense (income) [abstract]
Current income tax expenses (recoveries)	$ 320	$ (323)
Deferred income tax expenses (recoveries)	(326)	3,034
Total income tax expenses (recoveries)	$ (6)	$ 2,711

The amount of income tax relating to amounts recognised in other comprehensive income. [Refer: Other comprehensive income]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 12
-IssueDate 2023-01-01
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-Subparagraph ab
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-URIDate 2023-03-23

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2023-01-01
-Paragraph 90
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2023-en-r&anchor=para_90&doctype=Standard
-URIDate 2023-03-23

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