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Fair Value Measurements - Carrying Amount and Fair Values of the Company's Assets and Liabilities Measured on a Recurring Basis (Detail) - Recurring [Member] - USD ($) $ in Millions | Sep. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Carrying Amount [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Emission Trading Scheme Credits [Member] |  |
Derivatives (Level 1 measurement): |  |
Derivatives asset | $ 2.6 | $ 3.9
Carrying Amount [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Foreign Currency Forward Exchange Contracts [Member] |  |
Derivatives (Level 1 measurement): |  |
Derivatives asset | 4.1 | 1.5
Carrying Amount [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |
Non-financial liabilities (Level 3 measurement): |  |
Acquisition-related contingent consideration | 8.2 | 20.1
Fair Value [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Emission Trading Scheme Credits [Member] |  |
Derivatives (Level 1 measurement): |  |
Derivatives asset | 2.6 | 3.9
Fair Value [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Foreign Currency Forward Exchange Contracts [Member] |  |
Derivatives (Level 1 measurement): |  |
Derivatives asset | 4.1 | 1.5
Fair Value [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |
Non-financial liabilities (Level 3 measurement): |  |
Acquisition-related contingent consideration | $ 8.2 | $ 20.1

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