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v3.24.0.1

Variable Interest Entity: (Details) $ in Millions |  | 12 Months Ended
--- | --- | ---
Apr. 14, 2016 | Dec. 31, 2023 USD ($) MW | Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($)
Variable Interest Entity [Line Items] |  |  |  |
Variable Interest Entity, Qualitative or Quantitative Information, Ownership Percentage | 49.90% |  |  |
Net income attributable to non-controlling interest |  | $ (13.8) | $ (12.4) | $ (14.5)
Number of Days Following the End of the Quarter When Distributions of Net Income Attributable to this Non-controlling Interest are Due |  | 30 days |  |
Current assets |  | $ 826.6 | 1,071.7 |
Property, plant and equipment |  | 7,119.3 | 6,798.0 |
Current liabilities |  | 1,185.1 | 1,666.7 |
Variable Interest Entity, Primary Beneficiary |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Current assets |  | 15.1 | 12.8 |
Property, plant and equipment |  | 166.8 | 178.8 |
Current liabilities |  | 4.8 | 5.4 |
Power Generation |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Net income attributable to non-controlling interest |  | $ (13.8) | $ (12.4) | $ (14.5)
Pueblo Airport Generation | Subsidiary of Common Parent |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Electric Generation Capacity, Megawatts | MW |  | 200 |  |

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