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Pension and Post-Employment Benefits - Plan Net Pension Credit (Detail) - United Kingdom Plan [Member] $ in Millions	12 Months Ended
	Dec. 31, 2024 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Service cost/(credit)	$ 2.4
Interest cost on PBO	0.0
Expected return on plan assets	0.0
Amortization of prior service credit	0.0
Amortization of actuarial net losses	0.0
Net periodic cost	$ 2.4

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