Interest Income and Expense - Details of Interest Income from Financial Assets (Parenthetical) (Detail) - CAD ($) $ in Millions	3 Months Ended	6 Months Ended
Apr. 30, 2022	Jan. 31, 2022	Apr. 30, 2021	Apr. 30, 2022	Apr. 30, 2021
Expenses by nature [abstract]
Interest expense on lease liabilities	$ 26	$ 27	$ 27	$ 53	$ 54

The amount of interest expense on lease liabilities. [Refer: Lease liabilities]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 16
-IssueDate 2021-01-01
-Paragraph 53
-Subparagraph b
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2021-en-r&anchor=para_53_b&doctype=Standard
-URIDate 2021-03-24

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