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PENSION AND POST-RETIREMENT PLANS - AMOUNTS INCLUDED IN FINANCIAL STATEMENTS (Details) - USD ($) $ in Millions | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Employee benefit plans |  |  |
Non-current assets | $ 49.0 | $ 34.8 |
Non-current liabilities | (21.3) | (21.8) |
Pension Benefits |  |  |
Employee benefit plans |  |  |
Projected benefit obligations | 192.2 | 193.1 | $ 187.4
Fair value of plan assets at end of year | 241.2 | 227.9 | 206.3
Pension Benefits | Qualified Plan |  |  |
Employee benefit plans |  |  |
Non-current assets | 49.0 | 34.8 |
Total | 49.0 | 34.8 |
Net (loss) gain, net of taxes | (14.0) | (20.3) |
Total | (14.0) | (20.3) |
Pension Benefits | Nonqualified Plan |  |  |
Employee benefit plans |  |  |
Current liabilities | (0.4) | (1.2) |
Non-current liabilities | (4.0) | (3.4) |
Total | (4.4) | (4.6) |
Net (loss) gain, net of taxes | (0.4) | (0.2) |
Total | (0.4) | (0.2) |
Post-retirement benefits |  |  |
Employee benefit plans |  |  |
Projected benefit obligations | $ 18.4 | 19.5 | $ 15.3
Amortization period of unrecognized gains and losses | 5 years |  |
Post-retirement benefits | Qualified Plan |  |  |
Employee benefit plans |  |  |
Current liabilities | $ (1.1) | (1.1) |
Non-current liabilities | (17.3) | (18.4) |
Total | (18.4) | (19.5) |
Net (loss) gain, net of taxes | 2.5 | 2.7 |
Prior service credit, net of taxes | 5.6 | 8.3 |
Total | $ 8.1 | $ 11.0 |

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