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Benefit Plans - Components of Net Periodic Benefit Cost (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023
Pension benefits |  |  |
Net periodic benefit cost: |  |  |
Service cost | $ 1.3 | $ 1.2 | $ 1.1
Interest cost | 2.4 | 2.1 | 2.4
Expected return on plan assets | (1.2) | (1.3) | (1.2)
Amortization of actuarial loss (gain) | 0.9 | 0.6 | 0.6
Settlement loss | 0.0 | 0.0 | 0.1
Other | 0.0 | 1.0 | 0.3
Net periodic benefit cost | 3.4 | 3.6 | 3.3
Other changes in plan assets and benefit obligations recognized in OCI, pre-tax: |  |  |
Net (gain) loss arising during period | (3.4) | (0.7) | (1.4)
Amortization of actuarial (loss) gain | (0.9) | (0.6) | (0.3)
Settlement loss | 0.0 | 0.0 | (0.1)
Foreign currency translation | 0.7 | (0.2) | 0.7
Other | 0.0 | 0.0 | 0.4
Total recognized in OCI | (3.6) | (1.5) | (0.7)
Total recognized in net periodic benefit cost and OCI | (0.2) | 2.1 | 2.6
Pension benefits | United States |  |  |
Net periodic benefit cost: |  |  |
Net periodic benefit cost | 0.4 | 1.1 | 0.8
Pension benefits | International plans |  |  |
Net periodic benefit cost: |  |  |
Net periodic benefit cost | 3.0 | 2.5 | 2.5
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) | (1.3) | (1.6) | (2.0)
Settlement loss | 0.0 | 0.0 | 0.0
Other | 0.0 | 0.0 | 0.4
Net periodic benefit cost | (1.1) | (1.4) | (1.4)
Other changes in plan assets and benefit obligations recognized in OCI, pre-tax: |  |  |
Net (gain) loss arising during period | (0.3) | (0.5) | (0.5)
Amortization of actuarial (loss) gain | 1.3 | 1.6 | 2.0
Settlement loss | 0.0 | 0.0 | 0.0
Foreign currency translation | 0.0 | 0.0 | 0.0
Other | 0.0 | 0.0 | 0.0
Total recognized in OCI | 1.0 | 1.1 | 1.5
Total recognized in net periodic benefit cost and OCI | (0.1) | (0.3) | 0.1
Other retirement benefits | United States |  |  |
Net periodic benefit cost: |  |  |
Net periodic benefit cost | (1.1) | (1.4) | (1.4)
Other retirement benefits | International plans |  |  |
Net periodic benefit cost: |  |  |
Net periodic benefit cost | $ 0.0 | $ 0.0 | $ 0.0

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