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Pension and Post-Employment Benefits - Additional Information (Detail) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
	Sep. 30, 2024	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Defined Benefit Plan Disclosure [Line Items]
Pension scheme settlement charge		$ 155.6	$ 0.0	$ 0.0
Pension asset		2.4	35.1
Annual cash contribution		0.0	0.0
Income tax expense		(5.6)	(35.3)	(51.6)
Other Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Amount of contributions to defined contribution schemes		13.9	12.9
United Kingdom Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Pension asset		2.5	459.2	$ 452.1
Funds to cover pension related costs	$ 8.4	(8.4)	$ 0.0
Income tax expense		$ (2.1)
Percentage of asset allocation, actual		100.00%	100.00%	100.00%
United Kingdom Plan [Member] | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Projected Benefit Obligation		$ 0.1	$ 424.1	$ 404.0
Europe [Member] | Performance Chemicals [Member]
Defined Benefit Plan Disclosure [Line Items]
Post-employment obligations European businesses		4.1	4.2
France [Member]
Defined Benefit Plan Disclosure [Line Items]
Amount of unrecognized actuarial net losses, net of tax		$ 0.2	$ 0.3

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Amount of asset, recognized in statement of financial position, for overfunded defined benefit pension and other postretirement plans.

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