Securities - Summary of Securities (Parenthetical) (Detail) - CAD ($) $ in Millions	3 Months Ended
Apr. 30, 2021	Oct. 31, 2020
Disclosure of detailed information about financial instruments [line items]
Sale of securities measured at amortized cost	$ 0	$ 0

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

No definition available.

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