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Securities - Summary of Interest and Dividend Income and Gains on Securities (Detail) - Insurance products [member] - CAD ($) $ in Millions | 12 Months Ended
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Oct. 31, 2025 | Oct. 31, 2024
Disclosure In Tabular Form Of Interest And Dividend Income On Securities And Gains On Securities In Respect Of Insurance Business [Line Items] |  |  |
Interest and dividend income |  | $ 546 | $ 515
Gains from securities designated at FVTPL | [1] | 374 | 1,270
Realized gains from FVOCI securities |  |  | 1
Total interest and dividend income and gains held in our Insurance business |  | $ 920 | $ 1,786
[1] | Gains (losses) on these securities may be offset by certain (losses) gains from changes in insurance-related liabilities, as described above under Securities Designated at FVTPL.

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