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Fair Value Measurements and Trading-Related Revenue - Summary of Fair Value Measurement of Assets And Liabilities (Parenthetical) (Detail) - CAD ($) $ in Millions | 12 Months Ended
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Oct. 31, 2025 | Oct. 31, 2024
Disclosure Of Fair Value Of Financial Instruments [Line Items] |  |
Interest expense for liabilities | $ 42,050 | $ 46,517
Interest expense for liabilities carried at fair value [member] |  |
Disclosure Of Fair Value Of Financial Instruments [Line Items] |  |
Interest expense for liabilities | 3,476 | 2,774
Interest expense for liabilities carried at amortized cost [member] |  |
Disclosure Of Fair Value Of Financial Instruments [Line Items] |  |
Interest expense for liabilities | $ 38,574 | $ 43,743

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- Definition The amount of expense arising from interest. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 8 -IssueDate 2024-01-01 -Paragraph 28 -Subparagraph e -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=8&code=ifrs-tx-2024-en-r&anchor=para_28_e&doctype=Standard -URIDate 2024-03-27 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 12 -IssueDate 2024-01-01 -Paragraph B13 -Subparagraph f -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=12&code=ifrs-tx-2024-en-r&anchor=para_B13_f&doctype=Appendix&subtype=B -URIDate 2024-03-27 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 8 -IssueDate 2024-01-01 -Paragraph 23 -Subparagraph d -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=8&code=ifrs-tx-2024-en-r&anchor=para_23_d&doctype=Standard -URIDate 2024-03-27 + Details
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