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Derivative Instruments - Schedule of Fair Value of Derivative Instruments (Parenthetical) (Detail) - CAD ($) $ in Millions	Oct. 31, 2025	Oct. 31, 2024
Hedging Derivatives [Member] | Interest rate contracts [member]
Disclosure Of Derivative Financial Instruments [Line Items]
Net fair value of bonds designated as fair value hedges	$ 0	$ 0

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Disclosure Of Derivative Financial Instruments [Line Items]

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Net fair value of bonds designated as fair value hedges.

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