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Employee Compensation - Pension and Other Employee Future Benefits - Summary of Current Life Expectancies Underlying the Amounts of the Defined Benefit Obligations (Detail) | Oct. 31, 2025 | Oct. 31, 2024
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Canada [member] | Retiring currently at age sixty five [member] | Male [member] |  |
Disclosure of defined benefit plans [line items] |  |
Life expectancy for members | 23.6 | 24
Canada [member] | Retiring currently at age sixty five [member] | Female [member] |  |
Disclosure of defined benefit plans [line items] |  |
Life expectancy for members | 24.7 | 24.3
Canada [member] | Currently aged forty five and retiring at age sixty five [member] | Male [member] |  |
Disclosure of defined benefit plans [line items] |  |
Life expectancy for members | 24.5 | 24.9
Canada [member] | Currently aged forty five and retiring at age sixty five [member] | Female [member] |  |
Disclosure of defined benefit plans [line items] |  |
Life expectancy for members | 25.6 | 25.2
United States [member] | Retiring currently at age sixty five [member] | Male [member] |  |
Disclosure of defined benefit plans [line items] |  |
Life expectancy for members | 22 | 22
United States [member] | Retiring currently at age sixty five [member] | Female [member] |  |
Disclosure of defined benefit plans [line items] |  |
Life expectancy for members | 23.4 | 23.3
United States [member] | Currently aged forty five and retiring at age sixty five [member] | Male [member] |  |
Disclosure of defined benefit plans [line items] |  |
Life expectancy for members | 23.2 | 23.2
United States [member] | Currently aged forty five and retiring at age sixty five [member] | Female [member] |  |
Disclosure of defined benefit plans [line items] |  |
Life expectancy for members | 24.6 | 24.5

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