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v3.23.3

Operations and Significant Accounting Policies - Narrative (Details) $ in Millions | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2023 USD ($) | Sep. 30, 2022 USD ($) | Sep. 30, 2023 USD ($) MW | Sep. 30, 2022 USD ($) | Dec. 31, 2022 USD ($)
Non-Controlling Interest Details [Line Items] |  |  |  |  |
Goodwill | $ | $ 154.9 |  | $ 154.9 |  | $ 154.9
Net Loss Attributable to Non-Controlling Interest | $ | (16.3) | $ (6.9) | $ (47.7) | $ (43.5) |
Revision of Prior Period, Error Correction, Adjustment |  |  |  |  |
Non-Controlling Interest Details [Line Items] |  |  |  |  |
Net Loss Attributable to Non-Controlling Interest | $ | $ 5.7 |  |  |  | $ 3.6
Glen Ullin Energy Center |  |  |  |  |
Non-Controlling Interest Details [Line Items] |  |  |  |  |
Generating capacity subject to tax equity financing |  |  | 106 |  |
South Peak |  |  |  |  |
Non-Controlling Interest Details [Line Items] |  |  |  |  |
Generating capacity subject to tax equity financing |  |  | 80 |  |
Diamond Spring |  |  |  |  |
Non-Controlling Interest Details [Line Items] |  |  |  |  |
Generating capacity subject to tax equity financing |  |  | 303 |  |
Caddo |  |  |  |  |
Non-Controlling Interest Details [Line Items] |  |  |  |  |
Generating capacity subject to tax equity financing |  |  | 303 |  |
Nobles 2 |  |  |  |  |
Non-Controlling Interest Details [Line Items] |  |  |  |  |
Generating capacity subject to tax equity financing |  |  | 250 |  |

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