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Employee Compensation - Pension and Other Employee Future Benefits - Summary of Changes in Number of Key Assumption (Parenthetical) (Detail) - Defined benefit expenses [member] - Other employee future benefit plans [member] | Oct. 31, 2025 | Oct. 31, 2024
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Disclosure of defined benefit plans [line items] |  |  |
Assumed overall health care cost trend rate | [1] | 4.80% | 4.80%
2041 [Member] |  |  |
Disclosure of defined benefit plans [line items] |  |  |
Assumed overall health care cost trend rate |  | 4.00% | 4.00%
[1] | Trending to 4.0% in 2041 and remaining at that level thereafter.

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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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- Details
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