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Post-Employment Benefits - Summary of Defined Benefit obligation and Plan Assets by Region (Detail) - CAD ($) $ in Millions | Oct. 31, 2025 | Oct. 31, 2024
--- | --- | ---
Pension plan [member] |  |
Defined benefit obligation |  |
Defined benefit obligation at the end of year | $ 8,260 | $ 7,942
Plan assets |  |
Plan assets at the end of year | 9,975 | 9,326
Pension plan [member] | Canada plan [member] |  |
Defined benefit obligation |  |
Defined benefit obligation at the end of year | 7,592 | 7,291
Plan assets |  |
Plan assets at the end of year | 9,006 | 8,441
Pension plan [member] | U.S., and the Caribbean plans [member] |  |
Defined benefit obligation |  |
Defined benefit obligation at the end of year | 668 | 651
Plan assets |  |
Plan assets at the end of year | 969 | 885
Other post employment benefit plans [member] |  |
Defined benefit obligation |  |
Defined benefit obligation at the end of year | 420 | 419
Other post employment benefit plans [member] | Canada plan [member] |  |
Defined benefit obligation |  |
Defined benefit obligation at the end of year | 391 | 389
Other post employment benefit plans [member] | U.S., and the Caribbean plans [member] |  |
Defined benefit obligation |  |
Defined benefit obligation at the end of year | $ 29 | $ 30

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- Definition Defined benefit obligation. + References No definition available. + Details
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- Definition Defined benefit plan assets. + References No definition available. + Details
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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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- Details
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- Details
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- Details
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- Details
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