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Retirement Benefit Plans - Accumulated Benefit Obligations (Details) - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023
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UNITED STATES | Supplemental Employee Retirement Plan |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |
Accumulated benefit obligation | $ 0.8 | $ 0.9
Non-U.S. Plan | U.K. Pension Plan | Pension Plan |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |
Accumulated benefit obligation | 6.3 | 6.2
Non-U.S. Plan | German Pension Plan | Pension Plan |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |
Accumulated benefit obligation | 0.9 | 1.0
Non-U.S. Plan | French Pension Plan | Pension Plan |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |
Accumulated benefit obligation | 0.5 | 0.4
Non-U.S. Plan | Italian Pension Plan | Pension Plan |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |
Accumulated benefit obligation | $ 2.4 | $ 2.5

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