Financial Instruments - Summary of Fair Value Hierarchy of Instruments Carried at Fair Value on a Recurring Basis (Parenthetical) (Detail) - CAD ($) $ in Millions	Jan. 31, 2025	Oct. 31, 2024
Gross carrying amount [member]
Disclosure of fair value measurement of assets [line items]
Investment securities measured at amortized cost	$ 28,494	$ 29,412

The amount of financial assets at amortised cost. The amortised cost is the amount at which financial assets are measured at initial recognition minus principal repayments, plus or minus the cumulative amortisation using the effective interest method of any difference between that initial amount and the maturity amount, and adjusted for any impairment. [Refer: Financial assets]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2024-01-01
-Paragraph 8
-Subparagraph f
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2024-en-r&anchor=para_8_f&doctype=Standard
-URIDate 2024-03-27

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