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Pension and Post-Employment Benefits - Fair Value of Pension Assets (Detail) - USD ($) $ in Millions | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Fair value of pension assets |  |
Total plan assets | $ 35.1 | $ 48.1
Non-US [Member] |  |
Fair value of pension assets |  |
Debt securities | 443.4 | 436.1
Cash | 15.8 | 16.0
Total plan assets | 459.2 | 452.1
Non-US [Member] | Debt Securities Issued by Non-U.S. Government and Government Agencies [Member] |  |
Fair value of pension assets |  |
Debt securities | 4.7 | 4.3
Non-US [Member] | Corporate Debt Securities [Member] |  |
Fair value of pension assets |  |
Debt securities | 0.0 | 0.0
Non-US [Member] | Insurance Contracts [Member] |  |
Fair value of pension assets |  |
Debt securities | 438.7 | 431.8
Non-US [Member] | Other Financial Derivatives [Member] |  |
Fair value of pension assets |  |
Debt securities | 0.0 |
Non-US [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] |  |
Fair value of pension assets |  |
Debt securities | 4.7 | 4.3
Cash | 15.8 | 16.0
Total plan assets | 20.5 | 20.3
Non-US [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Debt Securities Issued by Non-U.S. Government and Government Agencies [Member] |  |
Fair value of pension assets |  |
Debt securities | 4.7 | 4.3
Non-US [Member] | Significant Other Observable Inputs (Level 2) [Member] |  |
Fair value of pension assets |  |
Debt securities | 0.0 | 0.0
Total plan assets | 0.0 | 0.0
Non-US [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |
Fair value of pension assets |  |
Debt securities | 438.7 | 431.8
Total plan assets | 438.7 | 431.8
Non-US [Member] | Significant Unobservable Inputs (Level 3) [Member] | Insurance Contracts [Member] | Other Asset Backed Securitites [Member] |  |
Fair value of pension assets |  |
Debt securities | $ 438.7 | $ 431.8

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- Definition Amount of asset, recognized in statement of financial position, for overfunded defined benefit pension and other postretirement plans. + 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/2009/role/commonPracticeRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(10)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.6-04(7)(b)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479617/946-210-S99-1 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480535/715-20-45-2 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -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 6: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(10)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1 + Details
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- Definition Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee. + 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 (d)(iv)(02) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(ii) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(01) -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 1 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 6: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(ii) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 7: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(01) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 + Details
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