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Employee Benefit Plans - Defined Benefit Pension Plans Weighted-Average Asset Allocations (Detail) - Foreign Plans [Member]	Sep. 30, 2025	Sep. 30, 2024
Defined Benefit Plan Disclosure [Line Items]
Equity securities	19.00%	19.00%
Debt securities	32.00%	33.00%
Real estate	12.00%	11.00%
Cash and other securities	37.00%	37.00%
Total	100.00%	100.00%

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Defined benefit plan, cash and other securities.

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Percentage of defined benefit plan debt securities.

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Percentage of defined benefit plan equity securities.

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Percentage of defined benefit plan real estate.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Percentage of actual investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

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