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Employee Compensation - Pension and Other Employee Future Benefits - Summary of Weighted-average Assumptions (Parenthetical) (Detail) | Oct. 31, 2025 | Oct. 31, 2024
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Pension Plans [member] | Current service costs [member] |  |  |
Disclosure of defined benefit plans [line items] |  |  |
Actuarial assumption of discount rates |  | 4.90% | 5.60%
Pension Plans [member] | Defined Benefit Expenses [Member] |  |  |
Disclosure of defined benefit plans [line items] |  |  |
Actuarial assumption of discount rates | [1],[2] | 4.90% | 5.80%
Pension Plans [member] | Defined Benefit Obligation [Member] |  |  |
Disclosure of defined benefit plans [line items] |  |  |
Actuarial assumption of discount rates |  | 4.80% | 4.90%
Other employee future benefit plans [member] | Current service costs [member] |  |  |
Disclosure of defined benefit plans [line items] |  |  |
Actuarial assumption of discount rates |  | 5.00% | 5.70%
Other employee future benefit plans [member] | Defined Benefit Expenses [Member] |  |  |
Disclosure of defined benefit plans [line items] |  |  |
Assumed overall health care cost trend rate | [3] | 4.80% | 4.80%
Actuarial assumption of discount rates | [1],[2] | 4.80% | 5.70%
Other employee future benefit plans [member] | Defined Benefit Expenses [Member] | 2041 [Member] |  |  |
Disclosure of defined benefit plans [line items] |  |  |
Assumed overall health care cost trend rate |  | 4.00% | 4.00%
Other employee future benefit plans [member] | Defined Benefit Obligation [Member] |  |  |
Disclosure of defined benefit plans [line items] |  |  |
Assumed overall health care cost trend rate | [3] | 4.70% | 4.80%
Actuarial assumption of discount rates |  | 4.70% | 4.80%
Other employee future benefit plans [member] | Defined Benefit Obligation [Member] | 2041 [Member] |  |  |
Disclosure of defined benefit plans [line items] |  |  |
Assumed overall health care cost trend rate |  | 4.00% |
[1] | The other employee future benefit plans current service cost was calculated using a separate discount rate of 5.0% and 5.7% for 2025 and 2024, respectively.
[2] | The pension benefit current service cost was calculated using a separate discount rate of 4.9% and 5.6% for 2025 and 2024, respectively.
[3] | Trending to 4.0% in 2041 and remaining at that level thereafter.

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- Definition The discount rate used as the 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 Medical cost trend rate used as 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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