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Retirement Plans - Defined Benefit Plan, Fair Value Measurement of Plan Assets (Parenthetical) (Detail) - Mutual Fund [Member] | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
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Large Cap US Companies Common Stock [Member] | Retiree Healthcare Plan [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Components of plan asset categories | 47.00% |  | 41.00%
International Growth Companies [Member] | Retiree Healthcare Plan [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Components of plan asset categories | 18.00% |  | 29.00%
International Growth Companies [Member] | Non-U.S. Pension Plans [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Components of plan asset categories |  | 25.00% | 18.00%
Fixed Income Bonds [Member] | Retiree Healthcare Plan [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Components of plan asset categories | 35.00% |  | 30.00%
International Bonds [Member] | Non-U.S. Pension Plans [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Components of plan asset categories |  | 71.00% | 76.00%
Other Investment Companies [Member] | Non-U.S. Pension Plans [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Components of plan asset categories |  | 4.00% | 7.00%

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- Definition 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. + References No definition available. + Details
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- Definition The percentage of the fair value of investment to the fair value of total plan asset category held as of the measurement date. + References No definition available. + Details
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