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Post-Employment Benefits - Summary of Longevities Underlying Values of Defined Benefit Obligation (Detail) - Canada plan [member] | 12 Months Ended
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Oct. 31, 2025 | Oct. 31, 2024
Longevity at age 65 for current retired members [member] | Male [member] |  |
Disclosure of defined benefit plans [line items] |  |
Longevity (in years) | 23 years 7 months 6 days | 23 years 7 months 6 days
Longevity at age 65 for current retired members [member] | Female [member] |  |
Disclosure of defined benefit plans [line items] |  |
Longevity (in years) | 24 years 8 months 12 days | 24 years 8 months 12 days
Longevity at age 65 for current members aged 45 [member] | Male [member] |  |
Disclosure of defined benefit plans [line items] |  |
Longevity (in years) | 24 years 6 months | 24 years 6 months
Longevity at age 65 for current members aged 45 [member] | Female [member] |  |
Disclosure of defined benefit plans [line items] |  |
Longevity (in years) | 25 years 7 months 6 days | 25 years 7 months 6 days

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- Definition The life expectancy after retirement used as a significant actuarial assumption to determine the present value of a defined benefit obligation. [Refer: Defined benefit obligation, at present value; Actuarial assumptions [domain]] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 19 -IssueDate 2024-01-01 -Paragraph 144 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2024-en-r&anchor=para_144&doctype=Standard -URIDate 2024-03-27 + Details
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- Definition Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table. + References No definition available. + 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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- Details
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