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v3.23.3

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, 2023 | Dec. 31, 2022
--- | --- | ---
Carrying Amount [Member] |  |
Non-derivatives: |  |
Cash and cash equivalents | $ 207.2 | $ 147.1
Carrying Amount [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Foreign Currency Forward Exchange Contracts [Member] |  |
Derivatives (Level 1 measurement): |  |
Derivative asset | 1.0 | 0.0
Derivatives (Level 1 measurement): |  |
Foreign currency forward exchange contracts | 0.0 | 0.5
Carrying Amount [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Emission Trading Scheme Credits [Member] |  |
Derivatives (Level 1 measurement): |  |
Derivative asset | 3.2 | 2.7
Carrying Amount [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |
Non-financial liabilities (Level 3 measurement): |  |
Stock equivalent units | 17.4 | 26.4
Fair Value [Member] |  |
Non-derivatives: |  |
Cash and cash equivalents | 207.2 | 147.1
Fair Value [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Foreign Currency Forward Exchange Contracts [Member] |  |
Derivatives (Level 1 measurement): |  |
Derivative asset | 1.0 | 0.0
Derivatives (Level 1 measurement): |  |
Foreign currency forward exchange contracts | 0.0 | 0.5
Fair Value [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Emission Trading Scheme Credits [Member] |  |
Derivatives (Level 1 measurement): |  |
Derivative asset | 3.2 | 2.7
Fair Value [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |
Non-financial liabilities (Level 3 measurement): |  |
Stock equivalent units | $ 17.4 | $ 26.4

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