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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
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

X

- Definition

The mortality rate 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
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-URIDate 2024-03-27

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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.

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