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Employee Compensation - Pension and Other Employee Future Benefits - Summary of Pension and Other Employee Future Benefit Expenses (Parenthetical) (Detail) - CAD ($) $ in Millions | 12 Months Ended
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Oct. 31, 2025 | Oct. 31, 2024
Other employee future benefit plans [Member] |  |
Disclosure of defined benefit plans [line items] |  |
Net interest (income) expense on effect of asset ceiling | $ 6 | $ 3
Pension Plan [Member] |  |
Disclosure of defined benefit plans [line items] |  |
Net interest (income) expense on effect of asset ceiling | $ 0 | $ 0

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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 increase (decrease) in the net defined benefit liability (asset) resulting from the passage of time. [Refer: Interest expense; Net defined benefit liability (asset)] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2024-01-01 -Paragraph 141 -Subparagraph b -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2024-en-r&anchor=para_141_b&doctype=Standard -URIDate 2024-03-27 + Details
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- Details
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- Details
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