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Pension and Post-Employment Benefits - Reconciliation of Fair Value of Plan Assets Measured Using Significant Unobservable Inputs (Detail) - United Kingdom Plan [Member] - Significant Unobservable Inputs (Level 3) [Member] - Other Assets [Member] $ in Millions | 12 Months Ended
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Dec. 31, 2024 USD ($)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |
Beginning balance | $ 438.7
Realized/unrealized gains/(losses): |
Relating to assets still held at the reporting date | (2.2)
Purchases, issuances and settlements | (438.8)
Exchange effect | 2.3
Ending balance | $ 0.0

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