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Investment in ATC and ATC Holdco (Details-3) - ATC [Member] - Affiliated Entity [Member] - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2026 | Jun. 30, 2025 | Jun. 30, 2026 | Jun. 30, 2025 | Dec. 31, 2025
Receivables [Abstract] |  |  |  |  |
Other Receivables | $ 3.7 |  | $ 3.7 |  | $ 2.5
Operating Costs and Expenses [Abstract] |  |  |  |  |
Operating Costs and Expenses, Total | $ 11.2 | $ 10.2 | $ 22.4 | $ 20.4 |

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