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EQUITY INVESTMENTS - Investment in ATC (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Investments In ATC [Roll Forward] |  |  |  |
Equity Investment Balance as of December 31, 2024 |  |  | $ 340.1 |
Cash Investments |  |  | 18.3 | $ 5.8
Equity Earnings | $ 5.6 | $ 5.1 | 17.5 | 16.5
Equity Investment Balance as of September 30, 2025 | 357.7 | 337.9 | 357.7 | 337.9
Net loss attributable to non-controlling interest | 13.8 | $ 12.3 | 60.5 | $ 39.3
ATC |  |  |  |
Investments In ATC [Roll Forward] |  |  |  |
Equity Investment Balance as of December 31, 2024 |  |  | 194.4 |
Cash Investments |  |  | 18.3 |
Equity Earnings |  |  | 19.7 |
Distributed Earnings |  |  | (17.6) |
Amortization of the Remeasurement of Deferred Income Taxes |  |  | 1.0 |
Equity Investment Balance as of September 30, 2025 | 215.8 |  | 215.8 |
Nobles 2 |  |  |  |
Investments In ATC [Roll Forward] |  |  |  |
Equity Investment Balance as of December 31, 2024 |  |  | 145.7 |
Equity Earnings |  |  | (2.2) |
Distributed Earnings |  |  | (1.6) |
Equity Investment Balance as of September 30, 2025 | $ 141.9 |  | 141.9 |
Net loss attributable to non-controlling interest |  |  | $ 8.7 |

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