Fair Value Measurement - Changes in Fair Value of Financial Assets and Liabilities in Level 3 (Parenthetical) (Detail) - Level 3 of fair value hierarchy [member] - CAD ($) $ in Millions	Apr. 30, 2025	Jan. 31, 2025	Apr. 30, 2024
Disclosure of reconciliation of changes in fair value measurement assets liabilities [line items]
Deposits	$ 208	$ 210	$ 197
Bifurcated embedded derivative liabilities	111	166	156
Other liabilities designated at FVTPL	$ 11	$ 3	$ 27

Disclosure of reconciliation of changes in fair value measurement assets liabilities [line items].

No definition available.

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