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Insurance - Summary Of Fair Value Changes in Investment Securities (Detail) - CAD ($) $ in Millions | 12 Months Ended
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Oct. 31, 2025 | Oct. 31, 2024
Change In Fair Value Of Investment Contracts [Line Items] |  |
Fair value | $ 745 | $ 796
Notional amount due at contractual maturity | 1,278 | 1,336
Difference between fair value and amount due at contractual maturity | (533) | (540)
Change in fair value - gains (losses) recorded in the Consolidated Statement of Income | (35) | (86)
Change in fair value - (losses) due to own credit risk recorded in OCI (before tax) | 28 | (34)
Cumulative change in fair value - gains (losses) due to own credit risk recognized in AOCI (before tax) | $ 2 | $ (26)

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- Definition Increase decrease in investment contracts liabilities due to changes in fair value of investment contract liabilities. + References No definition available. + Details
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- Definition Investment contracts liabilities measured at fair value. + References No definition available. + Details
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- Definition The accumulated increase (decrease) in the fair value of financial liabilities that is attributable to changes in the credit risk of the liabilities. [Refer: Credit risk [member]; Market risk [member]; Increase (decrease) in fair value of financial liability, attributable to changes in credit risk of liability] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2024-01-01 -Paragraph 10 -Subparagraph a -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2024-en-r&anchor=para_10_a&doctype=Standard -URIDate 2024-03-27 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2024-01-01 -Paragraph 10A -Subparagraph a -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2024-en-r&anchor=para_10A_a&doctype=Standard -URIDate 2024-03-27 + Details
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- Definition The amount by which the carrying amount of a financial liability is more (less) than the amount that the entity would be contractually required to pay at maturity to the holder of the obligation. [Refer: Carrying amount [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2024-01-01 -Paragraph 10A -Subparagraph b -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2024-en-r&anchor=para_10A_b&doctype=Standard -URIDate 2024-03-27 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2024-01-01 -Paragraph 10 -Subparagraph b -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2024-en-r&anchor=para_10_b&doctype=Standard -URIDate 2024-03-27 + Details
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- Definition A component of equity representing the accumulated change in fair value of financial liabilities attributable to change in the credit risk of the liabilities. [Refer: Credit risk [member]; Financial liabilities] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2024-01-01 -Paragraph 78 -Subparagraph e -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2024-en-r&anchor=para_78_e&doctype=Standard -URIDate 2024-03-27 + Details
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