Cash and Deposits with Financial Institutions - Summary of Cash and Deposits with Financial Institutions (Detail) - CAD ($) $ in Millions		Jan. 31, 2026	Oct. 31, 2025	Jan. 31, 2025	Oct. 31, 2024
Disclosure Of Cash And Cash Equivalents [abstract]
Cash and non-interest-bearing deposits with financial institutions	[1]	$ 8,732	$ 10,256	$ 9,897	$ 9,406
Interest-bearing deposits with financial institutions		65,106	55,711
Total	[2]	$ 73,838	$ 65,967

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

[2] Net of allowances of $3 (October 31, 2025 – $4)