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Retirement and Postretirement Plans - Change in Benefit Obligations (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Salaried Plan |  |  |
Change in benefit obligation: |  |  |
Actuarial (gains) losses | $ 1.0 |  |
Pension |  |  |
Change in benefit obligation: |  |  |
Benefit obligation at the beginning of year | 688.6 | $ 666.6 |
Service cost | 9.2 | 10.4 | $ 14.2
Interest cost | 31.1 | 35.8 | 39.6
Actuarial (gains) losses | (24.6) | 32.8 |
Benefits paid | (48.2) | (53.8) |
Settlements | (118.2) | (6.0) |
Foreign currency translation adjustment | (0.8) | 2.8 |
Benefit obligation at the end of year | 537.1 | 688.6 | 666.6
Pension | United States of America | Bargaining Plan |  |  |
Change in benefit obligation: |  |  |
Benefit obligation at the beginning of year | 490.9 | 474.9 |
Service cost | 8.9 | 9.5 | 13.9
Interest cost | 25.4 | 25.9 | 31.1
Actuarial (gains) losses | (16.9) | 19.1 |
Benefits paid | (36.7) | (38.5) |
Settlements | 0.0 |  |
Benefit obligation at the end of year | 471.6 | 490.9 | 474.9
Pension | United States of America | Salaried Plan |  |  |
Change in benefit obligation: |  |  |
Benefit obligation at the beginning of year | 124.0 | 128.1 |
Service cost | 0.3 | 0.9 | 0.3
Interest cost | 2.3 | 6.7 | 6.5
Actuarial (gains) losses | (1.5) | 5.7 |
Benefits paid | (6.9) | (11.4) |
Settlements | (118.2) | (6.0) |
Benefit obligation at the end of year | 0.0 | 124.0 | 128.1
Pension | United States of America | Supplemental Plan |  |  |
Change in benefit obligation: |  |  |
Benefit obligation at the beginning of year | 16.5 | $ 15.5 |
Service cost | $ 0.0 |  |
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Interest Cost, Statement of Income or Comprehensive Income [Extensible Enumeration] | Liability, Defined Benefit Plan, Noncurrent | Liability, Defined Benefit Plan, Noncurrent |
Interest cost | $ 0.9 | $ 0.9 | 0.7
Actuarial (gains) losses | (0.7) | 0.7 |
Benefits paid | (0.6) | (0.6) |
Settlements | 0.0 |  |
Benefit obligation at the end of year | 16.1 | 16.5 | 15.5
Pension | United Kingdom | Pension Scheme |  |  |
Change in benefit obligation: |  |  |
Benefit obligation at the beginning of year | 56.7 | 47.7 |
Service cost | 0.0 |  |
Interest cost | 2.5 | 2.3 | 1.3
Actuarial (gains) losses | (5.1) | 7.3 |
Benefits paid | (4.0) | (3.3) |
Foreign currency translation adjustment | (0.8) | 2.7 |
Benefit obligation at the end of year | 49.3 | 56.7 | 47.7
Pension | Mexico | Pension Plan |  |  |
Change in benefit obligation: |  |  |
Benefit obligation at the beginning of year | 0.5 | 0.4 |
Actuarial (gains) losses | (0.4) |  |
Foreign currency translation adjustment | 0.0 | 0.1 |
Benefit obligation at the end of year | 0.1 | 0.5 | 0.4
Postretirement |  |  |
Change in benefit obligation: |  |  |
Benefit obligation at the beginning of year | 84.9 | 87.4 |
Service cost | 0.6 | 0.7 | 1.1
Interest cost | 4.3 | 4.7 | 3.4
Actuarial (gains) losses | (0.2) | 3.8 |
Benefits paid | (9.5) | (11.7) |
Benefit obligation at the end of year | $ 80.1 | $ 84.9 | $ 87.4

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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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- Definition Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit 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) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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- Definition Amount of payment to participant of defined benefit plan which decreases benefit obligation. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 60 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480266/715-60-50-4 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (a)(6) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
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- Definition Amount of foreign currency translation gain (loss) which (increases) decreases benefit obligation of defined benefit 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)(5) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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- Definition Amount of cost recognized for passage of time related to 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 (a)(2) -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 (h)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-6 + Details
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- Definition Amount of cost for actuarial present value of benefits attributed to service rendered by employee for 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/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 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (a)(1) -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 (h)(1) -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)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-6 + Details
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