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Retirement Benefit Obligations - Key Weighted Average Assumptions Used in Determining Benefit Plan Costs and Obligations (Detail) - Benefit Plan Costs [Member]	9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024
Defined Benefit Plan Disclosure [Line Items]
Discount Rate	5.60%	5.00%
Rate of Compensation Increase	3.00%	3.00%
Expected Long-term rate of return on plan assets	7.50%	7.50%

X

- Definition

Weighted average rate for present value of future retirement benefits cash flows, used to determine net periodic benefit cost of defined benefit plan.

+ References

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-Topic 715
-SubTopic 20
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-Section 50
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- Definition

Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan.

+ References

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- Definition

Weighted average rate of compensation increase used to determine net periodic benefit cost of defined benefit plan. Plan includes, but is not limited to, pay-related defined benefit plan.

+ References

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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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