Investment Securities - Summary of Analysis of Fair Value and Carrying Value of Investment Securities Measured at Amortized Cost (Parenthetical) (Detail) - CAD ($) $ in Millions	Jan. 31, 2026	Oct. 31, 2025
Debt securities [member]
Disclosure of financial assets [line items]
Allowance account for credit losses of financial assets	$ 1	$ 1

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table.

No definition available.

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