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Pension and Post-Employment Benefits - Plan Net Pension Credit (Detail) - GERMANY - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Service cost | $ (0.9) | $ (0.6) | $ (2.7) | $ (1.8)
Interest cost on projected benefit obligation | (5.1) | (2.4) | (15.0) | (7.8)
Expected return on plan assets | 6.5 | 3.8 | 19.0 | 12.3
Amortization of prior service cost | (0.2) | (0.1) | (0.4) | (0.4)
Amortization of actuarial net gains/(losses) | 0.6 | (0.1) | 1.6 | (0.4)
Net periodic benefit | $ 0.9 | $ 0.6 | $ 2.5 | $ 1.9

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