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Pension and Other Postemployment Benefits (Tables) | 9 Months Ended
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Sep. 30, 2025
Pension and Other Postemployment Benefits [Abstract] |
Net Periodic Benefit Expense | Pension and other postemployment benefits net periodic benefit expense:
| Defined Benefit Pension Plans |  | Postemployment Arrangements
| Nine Months Ended September 30, |  | Nine Months Ended September 30,
| 2025 |  | 2024 |  | 2025 |  | 2024
Service cost | $ | 3.7 |  |  | $ | 2.1 |  |  | $ | 1.6 |  |  | $ | 2.3 |
Interest cost | 6.1 |  |  | 4.9 |  |  | 4.1 |  |  | 4.4 |
Expected return on plan assets | (0.6) |  |  | (0.6) |  |  | — |  |  | — |
Amortization of prior service cost | 2.3 |  |  | 0.3 |  |  | 2.8 |  |  | 3.3 |
Amortization of actuarial losses | 0.7 |  |  | 0.6 |  |  | — |  |  | 0.2 |
Total net periodic benefit expense | $ | 12.2 |  |  | $ | 7.3 |  |  | $ | 8.5 |  |  | $ | 10.2 |

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- Definition Pension and Other Postemployment Benefits [Abstract] + References No definition available. + Details
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- Definition Tabular disclosure of the components of net benefit costs for pension plans and/or other employee benefit plans including service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) recognized due to settlements or curtailments. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (q) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-5 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 715 -SubTopic 20 -Subparagraph (h) -Name Accounting Standards Codification -Paragraph 1 -Section 50 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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