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PENSION AND POST-RETIREMENT PLANS - FAIR VALUE (Details) - Pension Benefits - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | --- | ---
Pension and Post-retirement Plans |  |  |
Total | $ 241.2 | $ 227.9 | $ 206.3
Fair Value Measurement |  |  |
Pension and Post-retirement Plans |  |  |
Total | 198.6 | 186.3 |
Total plan assets | 241.2 | 227.9 |
Fair Value Measurement | Cash |  |  |
Pension and Post-retirement Plans |  |  |
Total | 5.1 | 6.1 |
Fair Value Measurement | U S large-cap |  |  |
Pension and Post-retirement Plans |  |  |
Total | 90.9 | 82.8 |
Fair Value Measurement | U S mid and small-cap |  |  |
Pension and Post-retirement Plans |  |  |
Total | 50.2 | 46.0 |
Fair Value Measurement | International large-cap |  |  |
Pension and Post-retirement Plans |  |  |
Total | 7.1 | 7.1 |
Fair Value Measurement | U S Treasuries |  |  |
Pension and Post-retirement Plans |  |  |
Total | 20.0 | 19.2 |
Fair Value Measurement | Municipal bonds |  |  |
Pension and Post-retirement Plans |  |  |
Total | 0.2 | 0.2 |
Fair Value Measurement | Investment grade U S corporate bonds |  |  |
Pension and Post-retirement Plans |  |  |
Total | 24.9 | 24.7 |
Fair Value Measurement | Convertible Bonds |  |  |
Pension and Post-retirement Plans |  |  |
Total | 0.1 | 0.1 |
Fair Value Measurement | International Fixed Income |  |  |
Pension and Post-retirement Plans |  |  |
Total | 0.1 | 0.1 |
Fair Value Measurement | Quoted Prices in Active Markets (Level 1) |  |  |
Pension and Post-retirement Plans |  |  |
Total | 166.2 | 142.0 |
Fair Value Measurement | Quoted Prices in Active Markets (Level 1) | Cash |  |  |
Pension and Post-retirement Plans |  |  |
Total | 5.1 | 6.1 |
Fair Value Measurement | Quoted Prices in Active Markets (Level 1) | U S large-cap |  |  |
Pension and Post-retirement Plans |  |  |
Total | 90.9 | 82.8 |
Fair Value Measurement | Quoted Prices in Active Markets (Level 1) | U S mid and small-cap |  |  |
Pension and Post-retirement Plans |  |  |
Total | 50.2 | 46.0 |
Fair Value Measurement | Quoted Prices in Active Markets (Level 1) | International large-cap |  |  |
Pension and Post-retirement Plans |  |  |
Total | 7.1 | 7.1 |
Fair Value Measurement | Quoted Prices in Active Markets (Level 1) | U S Treasuries |  |  |
Pension and Post-retirement Plans |  |  |
Total | 12.9 |  |
Fair Value Measurement | Significant Observable Inputs (Level 2) |  |  |
Pension and Post-retirement Plans |  |  |
Total | 32.4 | 44.3 |
Fair Value Measurement | Significant Observable Inputs (Level 2) | U S Treasuries |  |  |
Pension and Post-retirement Plans |  |  |
Total | 7.1 | 19.2 |
Fair Value Measurement | Significant Observable Inputs (Level 2) | Municipal bonds |  |  |
Pension and Post-retirement Plans |  |  |
Total | 0.2 | 0.2 |
Fair Value Measurement | Significant Observable Inputs (Level 2) | Investment grade U S corporate bonds |  |  |
Pension and Post-retirement Plans |  |  |
Total | 24.9 | 24.7 |
Fair Value Measurement | Significant Observable Inputs (Level 2) | Convertible Bonds |  |  |
Pension and Post-retirement Plans |  |  |
Total | 0.1 | 0.1 |
Fair Value Measurement | Significant Observable Inputs (Level 2) | International Fixed Income |  |  |
Pension and Post-retirement Plans |  |  |
Total | 0.1 | 0.1 |
Fair Value Measurement | Investment measured at NAV |  |  |
Pension and Post-retirement Plans |  |  |
Total | $ 42.6 | $ 41.6 |

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