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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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- Definition Amount of liability, recognized in statement of financial position, for defined benefit pension plan, classified as noncurrent. Excludes other postretirement benefit plan. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 3 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480535/715-20-45-3 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(24)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 45 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480535/715-20-45-2 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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