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Retirement and Postretirement Plans - Amounts Recognized in the Balance Sheet (Details) - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023
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Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Non-current assets | $ 5.5 | $ 9.9
Current liabilities | (66.5) | (43.5)
Non-current liabilities | (110.2) | (160.5)
Pension |  |
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Non-current assets | 5.5 | 9.9
Current liabilities | (65.3) | (42.3)
Non-current liabilities | (80.7) | (130.6)
Total assets (liabilities) recognized | (140.5) | (163.0)
Pension | United States of America | Bargaining Plan |  |
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Current liabilities | (64.7) | (41.7)
Non-current liabilities | (65.2) | (114.5)
Total assets (liabilities) recognized | (129.9) | (156.2)
Pension | United States of America | Salaried Plan |  |
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Non-current assets | 0.0 | 5.6
Total assets (liabilities) recognized | 0.0 | 5.6
Pension | United States of America | Supplemental Plan |  |
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Current liabilities | (0.6) | (0.6)
Non-current liabilities | (15.5) | (15.9)
Total assets (liabilities) recognized | (16.1) | (16.5)
Pension | United Kingdom | Pension Scheme |  |
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Non-current assets | 5.3 | 4.3
Total assets (liabilities) recognized | 5.3 | 4.3
Pension | Mexico | Pension Plan |  |
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Non-current assets | 0.2 |
Non-current liabilities | 0.0 | (0.2)
Total assets (liabilities) recognized | 0.2 | (0.2)
Postretirement |  |
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Current liabilities | (1.2) | (1.2)
Non-current liabilities | (29.5) | (29.9)
Total assets (liabilities) recognized | $ (30.7) | $ (31.1)

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- Definition Amount of asset (liability), recognized in statement of financial position, for defined benefit pension and other postretirement plans. + References Reference 1: 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 2: 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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- Definition Amount of asset, recognized in statement of financial position, for overfunded defined benefit pension and other postretirement plans. + References Reference 1: 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/1943274/2147478546/942-210-S99-1 Reference 2: 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 3: 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/1943274/2147478777/944-210-S99-1 Reference 4: 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/1943274/2147479170/946-210-S99-1 Reference 5: 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 6: 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 7: 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 + Details
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