Cash and Deposits with Financial Institutions - Summary of Cash and Deposits with Financial Institutions (Detail) - CAD ($) $ in Millions		Apr. 30, 2022	Jan. 31, 2022	Oct. 31, 2021	Apr. 30, 2021	Jan. 31, 2021	Oct. 31, 2020
Disclosure Of Cash And Cash Equivalents [abstract]
Cash and non-interest-bearing deposits with financial institutions	[1]	$ 10,643	$ 10,563	$ 9,693	$ 7,940	$ 9,443	$ 11,123
Interest-bearing deposits with financial institutions		75,267	88,490	76,630
Total	[2]	$ 85,910	$ 99,053	$ 86,323

[1] Represents cash and non-interest-bearing deposits with financial institutions (refer to Note 5).

[2] Net of allowances of $0 (January 31, 2022 – $1; October 31, 2021 – $1).