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EQUITY INVESTMENTS - Investment in ATC (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2025 | Jun. 30, 2024 | Jun. 30, 2025 | Jun. 30, 2024
Investments In ATC [Roll Forward] |  |  |  |
Equity Investment Balance as of December 31, 2024 |  |  | $ 340.1 |
Cash Investments |  |  | 11.3 | $ 3.9
Equity Earnings | $ 5.9 | $ 5.9 | 11.9 | 11.4
Equity Investment Balance as of June 30, 2025 | 350.5 | 336.0 | 350.5 | 336.0
Net loss attributable to non-controlling interest | 25.3 | $ 13.3 | 46.7 | $ 27.0
ATC |  |  |  |
Investments In ATC [Roll Forward] |  |  |  |
Equity Investment Balance as of December 31, 2024 |  |  | 194.4 |
Cash Investments |  |  | 11.3 |
Equity Earnings |  |  | 12.9 |
Distributed Earnings |  |  | (12.3) |
Amortization of the Remeasurement of Deferred Income Taxes |  |  | 0.6 |
Equity Investment Balance as of June 30, 2025 | 206.9 |  | 206.9 |
Nobles 2 |  |  |  |
Investments In ATC [Roll Forward] |  |  |  |
Equity Investment Balance as of December 31, 2024 |  |  | 145.7 |
Equity Earnings |  |  | (1.0) |
Distributed Earnings |  |  | (1.1) |
Equity Investment Balance as of June 30, 2025 | $ 143.6 |  | 143.6 |
Net loss attributable to non-controlling interest |  |  | $ 7.3 |

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