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Securities - Additional Information (Detail) - CAD ($) $ in Millions | Oct. 31, 2025 | Oct. 31, 2024
--- | --- | ---
Disclosure of financial assets [line items] |  |
Fair value through profit or loss ("FVTPL") securities | $ 21,354 | $ 19,064
Amortized cost | 96,610 | 115,188
FVOCI Securities | 113,209 | 93,702
Debt securities [member] |  |
Disclosure of financial assets [line items] |  |
Amortized cost | 96,610 | 115,188
FVOCI Securities | 113,209 | 93,702
Allowance for credit losses of amortized cost | 4 | 3
Allowance for credit losses of FVOCI securities | 6 | 4
Mandatorily measured at fair value [member] |  |
Disclosure of financial assets [line items] |  |
Fair value through profit or loss ("FVTPL") securities | 7,818 | 6,850
Assets recognised | 1,136 | 900
Related to securities held by insurance subsidiaries [member] |  |
Disclosure of financial assets [line items] |  |
Fair value through profit or loss ("FVTPL") securities | $ 13,536 | $ 12,214

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