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v3.25.0.1

Pension and Post-Employment Benefits - Movements in PBO and Fair Value of Plan Assets (Detail) - USD ($) $ in Millions | 1 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2024 | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Change in PBO: |  |  |  |
Actuarial losses/(gains) |  | $ 21.3 | $ 17.5 | $ 69.9
Fair value of plan assets: |  |  |  |
Opening balance |  | 35.1 |  |
Closing balance |  | 2.4 | 35.1 |
United Kingdom Plan [Member] |  |  |  |
Fair value of plan assets: |  |  |  |
Opening balance |  | 459.2 | 452.1 |
Return of Funds to Cover Historic Expenses | $ 8.4 | (8.4) | 0.0 |
Benefits paid |  | (32.9) | (35.6) |
Actual return on assets |  | 1.5 | 17.9 |
Settlements |  | (419.2) | 0.0 |
Exchange effect |  | 2.3 | 24.8 |
Closing balance |  | 2.5 | 459.2 | 452.1
German Plan [Member] |  |  |  |
Change in PBO: |  |  |  |
Opening balance |  | 9.1 | 8.2 |
Interest cost |  | 0.3 | 0.3 | 0.1
Service cost/(credit) |  | 0.0 | 0.1 | 0.1
Benefits paid |  | (0.4) | (0.3) |
Actuarial losses/(gains) |  | 0.5 | 0.6 |
Exchange effect |  | (0.5) | 0.2 |
Closing balance |  | 9.0 | 9.1 | 8.2
Pension Benefit Obligation [Member] | United Kingdom Plan [Member] |  |  |  |
Change in PBO: |  |  |  |
Opening balance |  | 424.1 | 404.0 |
Interest cost |  | 18.6 | 19.6 |
Service cost/(credit) |  | (4.9) | 3.5 |
Benefits paid |  | (32.9) | (35.6) |
Plan amendments |  | 8.4 | 0.0 |
Actuarial losses/(gains) |  | 3.7 | 10.1 |
Settlements |  | (419.2) | 0.0 |
Exchange effect |  | 2.3 | 22.5 |
Closing balance |  | $ 0.1 | $ 424.1 | $ 404.0

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- Definition Amount of increase (decrease) in plan assets of defined benefit plan from actual return (loss) determined by change in fair value of plan assets adjusted for contributions, benefit payments, and other expenses. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 17 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480482/715-20-55-17 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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- Definition Amount of gain (loss) from change in actuarial assumptions which (increases) decreases benefit obligation of defined benefit plan. Assumptions include, but are not limited to, interest, mortality, employee turnover, salary, and temporary deviation from substantive plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (a)(4) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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