Securities - Summary of Securities (Parenthetical) (Detail) - CAD ($) $ in Millions	12 Months Ended
Oct. 31, 2022	Oct. 31, 2021
Disclosure of detailed information about financial instruments [line items]
Debt Securities, Available-for-sale, Amortized Cost	$ 1
Debt securities [member] \| Financial assets at amortised cost, category [member]
Disclosure of detailed information about financial instruments [line items]
Realized gain (loss) on disposal of debt securities	$ 1	$ 1

The gains (losses) on disposals of investments.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2021-01-01
-Paragraph 98
-Subparagraph d
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2021-en-r&anchor=para_98_d&doctype=Standard
-URIDate 2021-03-24

Name:	ifrs-full_GainsLossesOnDisposalsOfInvestments
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration