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EQUITY INVESTMENTS - Investment in ATC (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2024 | Sep. 30, 2023
Investments In ATC [Roll Forward] |  |  |  |
Equity Investment Balance as of December 31, 2023 |  |  | $ 331.2 |
Cash Investments |  |  | 5.8 | $ 6.6
Equity Earnings | $ 5.1 | $ 4.7 | 16.5 | 16.1
Equity Investment Balance as of September 30, 2024 | 337.9 |  | 337.9 |
Net loss attributable to non-controlling interest | 12.3 | $ 16.3 | 39.3 | $ 47.7
ATC |  |  |  |
Investments In ATC [Roll Forward] |  |  |  |
Equity Investment Balance as of December 31, 2023 |  |  | 179.7 |
Cash Investments |  |  | 5.8 |
Equity Earnings |  |  | 17.8 |
Distributed earnings |  |  | (14.0) |
Amortization of the Remeasurement of Deferred Income Taxes |  |  | 1.0 |
Equity Investment Balance as of September 30, 2024 | 190.3 |  | 190.3 |
Nobles 2 |  |  |  |
Investments In ATC [Roll Forward] |  |  |  |
Equity Investment Balance as of December 31, 2023 |  |  | 151.5 |
Equity Earnings |  |  | (1.3) |
Distributed earnings |  |  | (2.6) |
Equity Investment Balance as of September 30, 2024 | $ 147.6 |  | 147.6 |
Net loss attributable to non-controlling interest |  |  | $ 8.4 |

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