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Employee Compensation - Pension and Other Employee Future Benefits - Summary of Plan Information for Past Two Years (Detail) - CAD ($) $ in Millions | Oct. 31, 2025 | Oct. 31, 2024
--- | --- | ---
Disclosure of defined benefit plans [line items] |  |
Fair value of plan assets | $ 9,456 | $ 9,156
Pension Plans [member] |  |
Disclosure of defined benefit plans [line items] |  |
Defined benefit obligation | 8,582 | 8,365
Fair value of plan assets | 9,708 | 9,431
Net surplus (deficit) is compromised of: |  |
Net surplus (deficit), net of the effect of the asset ceiling | 1,126 | 1,063
Pension Plans [member] | Funded plans [member] |  |
Net surplus (deficit) is compromised of: |  |
Net surplus (deficit), net of the effect of the asset ceiling | 1,271 | 1,223
Pension Plans [member] | Unfunded plans [member] |  |
Net surplus (deficit) is compromised of: |  |
Net surplus (deficit), net of the effect of the asset ceiling | (145) | (160)
Pension Plans [member] | Before effect of asset ceiling [member] |  |
Net surplus (deficit) is compromised of: |  |
Net surplus (deficit), net of the effect of the asset ceiling | 1,126 | 1,066
Pension Plans [member] | Effect of asset ceiling [member] |  |
Net surplus (deficit) is compromised of: |  |
Net surplus (deficit), net of the effect of the asset ceiling | 0 | (3)
Other employee future benefit plans [member] |  |
Disclosure of defined benefit plans [line items] |  |
Defined benefit obligation | 950 | 954
Fair value of plan assets | 248 | 245
Net surplus (deficit) is compromised of: |  |
Net surplus (deficit), net of the effect of the asset ceiling | (776) | (819)
Other employee future benefit plans [member] | Funded plans [member] |  |
Net surplus (deficit) is compromised of: |  |
Net surplus (deficit), net of the effect of the asset ceiling | 87 | 44
Other employee future benefit plans [member] | Unfunded plans [member] |  |
Net surplus (deficit) is compromised of: |  |
Net surplus (deficit), net of the effect of the asset ceiling | (863) | (863)
Other employee future benefit plans [member] | Before effect of asset ceiling [member] |  |
Net surplus (deficit) is compromised of: |  |
Net surplus (deficit), net of the effect of the asset ceiling | (702) | (709)
Other employee future benefit plans [member] | Effect of asset ceiling [member] |  |
Net surplus (deficit) is compromised of: |  |
Net surplus (deficit), net of the effect of the asset ceiling | $ (74) | $ (110)

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- Definition The present value, without deducting any plan assets, of expected future payments required to settle the obligation resulting from employee service in the current and prior periods. [Refer: Plan assets, at fair value] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 19 -IssueDate 2024-01-01 -Paragraph 57 -Subparagraph a -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2024-en-r&anchor=para_57_a&doctype=Standard -URIDate 2024-03-27 + Details
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- Definition The fair value of defined benefit plan assets. Plan assets comprise assets held by a long-term employee benefit fund and qualifying insurance policies. [Refer: At fair value [member]] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 19 -IssueDate 2024-01-01 -Paragraph 57 -Subparagraph a -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2024-en-r&anchor=para_57_a&doctype=Standard -URIDate 2024-03-27 + Details
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- Definition The fair value of any plan assets, less the present value of the defined benefit obligation. [Refer: Plan assets [member]] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 19 -IssueDate 2024-01-01 -Paragraph 57 -Subparagraph a -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2024-en-r&anchor=para_57_a&doctype=Standard -URIDate 2024-03-27 + Details
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