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Insurance - Summary Of Fair Value Changes in Investment Securities (Detail) - CAD ($) $ in Millions	12 Months Ended
	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.

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- Definition

Investment contracts liabilities measured at fair value.

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- Definition

Notional amount due at contractual maturity.

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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
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-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2024-en-r&anchor=para_10_a&doctype=Standard
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
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-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2024-en-r&anchor=para_10A_a&doctype=Standard
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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
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-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2024-en-r&anchor=para_10A_b&doctype=Standard
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-Name IFRS
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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]

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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