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Benefit Plans - Components of Net Periodic Benefit Cost (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Pension benefits |  |  |
Net periodic benefit cost: |  |  |
Service cost | $ 1.2 | $ 1.1 | $ 1.5
Interest cost | 2.1 | 2.4 | 4.2
Expected return on plan assets | (1.3) | (1.2) | (6.1)
Amortization of actuarial loss (gain) | 0.6 | 0.6 | 1.3
Settlement loss | 0.0 | 0.1 | 52.2
Other | 1.0 | 0.3 | 1.0
Net periodic benefit cost | 3.6 | 3.3 | 54.1
Other changes in plan assets and benefit obligations recognized in OCI, pre-tax: |  |  |
Net (gain) loss arising during period | (0.7) | (1.4) | 16.0
Amortization of actuarial (loss) gain | (0.6) | (0.3) | (1.3)
Settlement loss | 0.0 | (0.1) | (52.2)
Foreign currency translation | (0.2) | 0.7 | (2.3)
Other | 0.0 | 0.4 | 0.0
Total recognized in OCI | (1.5) | (0.7) | (39.8)
Total recognized in net periodic benefit cost and OCI | 2.1 | 2.6 | 14.3
Pension benefits | United States |  |  |
Net periodic benefit cost: |  |  |
Net periodic benefit cost | 1.1 | 0.8 | 51.7
Pension benefits | International plans |  |  |
Net periodic benefit cost: |  |  |
Net periodic benefit cost | 2.5 | 2.5 | 2.4
Other retirement benefits |  |  |
Net periodic benefit cost: |  |  |
Service cost | 0.0 | 0.0 | 0.0
Interest cost | 0.2 | 0.2 | 0.2
Expected return on plan assets | 0.0 | 0.0 | 0.0
Amortization of actuarial loss (gain) | (1.6) | (2.0) | (1.9)
Settlement loss | 0.0 | 0.0 | 0.0
Other | 0.0 | 0.4 | 0.4
Net periodic benefit cost | (1.4) | (1.4) | (1.3)
Other changes in plan assets and benefit obligations recognized in OCI, pre-tax: |  |  |
Net (gain) loss arising during period | (0.5) | (0.5) | (2.0)
Amortization of actuarial (loss) gain | 1.6 | 2.0 | 1.9
Settlement loss | 0.0 | 0.0 | 0.0
Foreign currency translation | 0.0 | 0.0 | 0.0
Other | 0.0 | 0.0 | (0.4)
Total recognized in OCI | 1.1 | 1.5 | (0.5)
Total recognized in net periodic benefit cost and OCI | (0.3) | 0.1 | (1.8)
Other retirement benefits | United States |  |  |
Net periodic benefit cost: |  |  |
Net periodic benefit cost | (1.4) | (1.4) | (1.3)
Other retirement benefits | International plans |  |  |
Net periodic benefit cost: |  |  |
Net periodic benefit cost | $ 0.0 | $ 0.0 | $ 0.0

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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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- Definition Amount of expected return (loss) recognized in net periodic benefit (cost) credit, calculated based on expected long-term rate of return and market-related value of plan assets 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)(3) -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)(3) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-6 + Details
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