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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
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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