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Retirement and Postretirement Plans - Components of Net Periodic Benefit Cost (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Pension |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Service cost | $ 9.2 | $ 10.4 | $ 14.2
Interest cost | 31.1 | 35.8 | 39.6
Expected return on plan assets | (33.5) | (37.1) | (54.9)
Amortization of prior service cost | 1.2 | 1.3 | 1.3
Settlements | 0.0 | 0.0 |
Curtailments |  |  | (2.7)
Net remeasurement losses (gains) | 10.4 | 38.7 | (20.9)
Net Periodic Benefit Cost (Income) | 18.4 | 49.1 | (23.4)
Pension | United States of America | Bargaining Plan |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Service cost | 8.9 | 9.5 | 13.9
Interest cost | 25.4 | 25.9 | 31.1
Expected return on plan assets | (28.0) | (26.9) | (46.7)
Amortization of prior service cost | 1.2 | 1.3 | 1.3
Settlements | 0.0 | 0.0 |
Curtailments |  |  | (2.7)
Net remeasurement losses (gains) | 8.3 | 26.6 | (37.2)
Net Periodic Benefit Cost (Income) | 15.8 | 36.4 | (40.3)
Pension | United States of America | Salaried Plan |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Service cost | 0.3 | 0.9 | 0.3
Interest cost | 2.3 | 6.7 | 6.5
Expected return on plan assets | (2.4) | (7.5) | (5.0)
Curtailments |  |  | 0.0
Net remeasurement losses (gains) | 1.8 | 4.0 | 6.9
Net Periodic Benefit Cost (Income) | 2.0 | 4.1 | 8.7
Pension | United States of America | Supplemental Plan |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Service cost | 0.0 |  |
Interest cost | 0.9 | 0.9 | 0.7
Curtailments |  |  | 0.0
Net remeasurement losses (gains) | (0.7) | 0.6 | (6.5)
Net Periodic Benefit Cost (Income) | 0.2 | 1.5 | (5.8)
Pension | United Kingdom | Pension Scheme |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Service cost | 0.0 |  |
Interest cost | 2.5 | 2.3 | 1.3
Expected return on plan assets | (3.1) | (2.7) | (3.2)
Net remeasurement losses (gains) | 1.4 | 7.5 | 15.9
Net Periodic Benefit Cost (Income) | 0.8 | 7.1 | 14.0
Pension | Mexico | Pension Plan |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Net remeasurement losses (gains) | (0.4) |  | 0.0
Net Periodic Benefit Cost (Income) | (0.4) |  | 0.0
Postretirement |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Service cost | 0.6 | 0.7 | 1.1
Interest cost | 4.3 | 4.7 | 3.4
Expected return on plan assets | (2.9) | (3.4) | (3.4)
Amortization of prior service cost | (5.9) | (6.0) | (6.0)
Net remeasurement losses (gains) | (0.1) | 1.9 | (11.8)
Net Periodic Benefit Cost (Income) | $ (4.0) | $ (2.1) | $ (16.7)

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- Definition Amount of prior service cost (credit) 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)(5) -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)(5) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-6 + Details
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