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Securities - Summary of Securities (Parenthetical) (Detail) - CAD ($) $ in Millions | 12 Months Ended
--- | ---
Oct. 31, 2025 | Oct. 31, 2024
Disclosure of detailed information about financial instruments [line items] |  |
Debt securities, available-for-sale, amortized cost | $ 1 |
Debt securities [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Realized gain (loss) on disposal of debt securities | $ 0 | $ 0

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- Definition Available for sale debt securities amortized cost basis. + References No definition available. + Details
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Balance Type: | debit
Period Type: | instant

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- Definition Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table. + References No definition available. + Details
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- Definition The gains (losses) on disposals of investments. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2024-01-01 -Paragraph 98 -Subparagraph d -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2024-en-r&anchor=para_98_d&doctype=Standard -URIDate 2024-03-27 + Details
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- Details
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