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Pension and Post-Employment Benefits - Unfunded Defined Benefit Pension Plan (Detail) - German Plan [Member] - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023
Plan net pension charge: |  |  |
Service cost/(credit) | $ 0.0 | $ 0.0 | $ 0.1
Interest cost on PBO | 0.3 | 0.3 | 0.3
Amortization of actuarial net loss/(gain) | 0.0 | (0.2) | (0.5)
Net periodic cost/(benefit) | $ 0.3 | $ 0.1 | $ (0.1)
Plan assumptions at December 31, (%): |  |  |
Discount rate | 3.80% | 3.20% | 3.70%
Inflation rate | 2.25% | 2.25% | 2.25%
Rate of increase in compensation levels | 2.75% | 2.75% | 2.75%

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- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit of defined benefit plan. + 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 45 -Paragraph 3A -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480535/715-20-45-3A Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 18 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480482/715-20-55-18 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (h)(4) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a)(4) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-6 + Details
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