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Securities - Summary of Securities (Detail) - CAD ($) $ in Millions | Oct. 31, 2025 | Oct. 31, 2024
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Disclosure of detailed information about financial instruments [abstract] |  |
Securities measured and designated at FVOCI | $ 88,905 | $ 76,693
Securities measured at amortized cost | 65,471 | 71,610
Securities mandatorily measured and designated at FVTPL | 128,859 | 106,042
Total securities | $ 283,235 | $ 254,345

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