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Pension and Other Postretirement Benefits - Changes in Plan Assets & Benefit Obligation Recognized in OCI (pre-taxed) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net (gain) loss | $ (11.9) | $ (10.1) | $ (5.9)
Amortization of prior service benefit during the period | 0.2 | 0.1 | (1.2)
Pension |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net (gain) loss | (8.4) | (6.9) |
Net loss (gain) transferred due to acquisition | 0.0 | (4.5) |
Prior service cost (benefit) | 0.0 | 1.2 |
Amortization of net loss, including recognition due to settlement | (5.8) | (6.0) |
Amortization of prior service benefit during the period | 0.2 | 0.1 |
Exchange rates | (2.4) | (1.1) |
Total amount recognized in other comprehensive income (loss) | 0.0 | (3.6) |
Net periodic benefit cost | 8.9 | 9.4 | (5.3)
Total recognized in net periodic benefit cost and other comprehensive income (loss) | 8.9 | 5.8 |
OPEB |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net (gain) loss | (0.3) | (4.8) |
Net loss (gain) transferred due to acquisition | 0.0 | (0.2) |
Prior service cost (benefit) | 0.0 | 0.0 |
Amortization of net loss, including recognition due to settlement | (0.7) | (0.2) |
Amortization of prior service benefit during the period | 0.0 | 0.0 |
Exchange rates | 0.0 | (0.1) |
Total amount recognized in other comprehensive income (loss) | (0.4) | 4.3 |
Net periodic benefit cost | 4.8 | 4.1 | $ (5.8)
Total recognized in net periodic benefit cost and other comprehensive income (loss) | $ 4.4 | $ 8.4 |

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