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Equity Investments - Investment in ATC (Details) - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2024 | Mar. 31, 2023
Investments In ATC [Roll Forward] |  |
Equity Investment Balance as of December 31, 2023 | $ 331.2 |
Cash Investments | 1.6 | $ 0.8
Equity Earnings | 5.5 | 6.0
Equity Investment Balance as of March 31, 2024 | 333.1 |
Net Loss Attributable to Non-Controlling Interest | (13.7) | $ (20.6)
ATC |  |
Investments In ATC [Roll Forward] |  |
Equity Investment Balance as of December 31, 2023 | 179.7 |
Cash Investments | 1.6 |
Equity Earnings | 5.7 |
Distributed earnings | (4.6) |
Amortization of the Remeasurement of Deferred Income Taxes | 0.3 |
Equity Investment Balance as of March 31, 2024 | 182.7 |
Nobles 2 |  |
Investments In ATC [Roll Forward] |  |
Equity Investment Balance as of December 31, 2023 | 151.5 |
Equity Earnings | (0.2) |
Distributed earnings | (0.9) |
Equity Investment Balance as of March 31, 2024 | 150.4 |
Net Loss Attributable to Non-Controlling Interest | $ 3.0 |

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