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PENSION AND POST-RETIREMENT PLANS - FAIR VALUE (Details) - Pension Benefits - USD ($) $ in Millions | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | --- | ---
Pension and Post-retirement Plans |  |  |
Total | $ 238.9 | $ 212.8 | $ 194.8
Fair Value Measurement |  |  |
Pension and Post-retirement Plans |  |  |
Total | 195.1 | 170.9 |
Total plan assets | 239.5 | 212.8 |
Fair Value Measurement | Cash |  |  |
Pension and Post-retirement Plans |  |  |
Total | 10.7 | 3.8 |
Fair Value Measurement | U S large-cap |  |  |
Pension and Post-retirement Plans |  |  |
Total | 80.9 | 71.3 |
Fair Value Measurement | U S mid and small-cap |  |  |
Pension and Post-retirement Plans |  |  |
Total | 61.7 | 54.3 |
Fair Value Measurement | International large-cap |  |  |
Pension and Post-retirement Plans |  |  |
Total | 7.5 | 7.0 |
Fair Value Measurement | U S Treasuries |  |  |
Pension and Post-retirement Plans |  |  |
Total | 9.6 | 12.0 |
Fair Value Measurement | Investment grade U S corporate bonds |  |  |
Pension and Post-retirement Plans |  |  |
Total | 24.5 | 22.5 |
Fair Value Measurement | High-yield U.S. corporate bonds / Non-U.S. Bonds |  |  |
Pension and Post-retirement Plans |  |  |
Total | 0.2 |  |
Fair Value Measurement | Quoted Prices in Active Markets (Level 1) |  |  |
Pension and Post-retirement Plans |  |  |
Total | 160.8 | 68.9 |
Fair Value Measurement | Quoted Prices in Active Markets (Level 1) | Cash |  |  |
Pension and Post-retirement Plans |  |  |
Total | 10.7 | 3.8 |
Fair Value Measurement | Quoted Prices in Active Markets (Level 1) | U S large-cap |  |  |
Pension and Post-retirement Plans |  |  |
Total | 80.9 | 28.9 |
Fair Value Measurement | Quoted Prices in Active Markets (Level 1) | U S mid and small-cap |  |  |
Pension and Post-retirement Plans |  |  |
Total | 61.7 | 36.2 |
Fair Value Measurement | Quoted Prices in Active Markets (Level 1) | International large-cap |  |  |
Pension and Post-retirement Plans |  |  |
Total | 7.5 |  |
Fair Value Measurement | Significant Observable Inputs (Level 2) |  |  |
Pension and Post-retirement Plans |  |  |
Total | 34.3 | 102.0 |
Fair Value Measurement | Significant Observable Inputs (Level 2) | U S large-cap |  |  |
Pension and Post-retirement Plans |  |  |
Total |  | 42.4 |
Fair Value Measurement | Significant Observable Inputs (Level 2) | U S mid and small-cap |  |  |
Pension and Post-retirement Plans |  |  |
Total |  | 18.1 |
Fair Value Measurement | Significant Observable Inputs (Level 2) | International large-cap |  |  |
Pension and Post-retirement Plans |  |  |
Total |  | 7.0 |
Fair Value Measurement | Significant Observable Inputs (Level 2) | U S Treasuries |  |  |
Pension and Post-retirement Plans |  |  |
Total | 9.6 | 12.0 |
Fair Value Measurement | Significant Observable Inputs (Level 2) | Investment grade U S corporate bonds |  |  |
Pension and Post-retirement Plans |  |  |
Total | 24.5 | 22.5 |
Fair Value Measurement | Significant Observable Inputs (Level 2) | High-yield U.S. corporate bonds / Non-U.S. Bonds |  |  |
Pension and Post-retirement Plans |  |  |
Total | 0.2 |  |
Fair Value Measurement | Investment measured at NAV |  |  |
Pension and Post-retirement Plans |  |  |
Total | $ 44.4 | $ 41.9 |

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