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Acquisitions and Dispositions (Details) - SOUTHERN POWER CO $ in Millions | 1 Months Ended | 9 Months Ended
--- | --- | ---
Oct. 30, 2024 MW | Sep. 30, 2024 USD ($) MW
South Cheyenne Solar Facility |  |
Business Acquisition [Line Items] |  |
Nameplate capacity placed in service (in MWs) |  | 150
Approximate nameplate capacity |  | 150
Life output of plant (in years) |  | 20 years
Millers Branch Solar Development Phase 1 |  |
Business Acquisition [Line Items] |  |
Approximate nameplate capacity |  | 200
Life output of plant (in years) |  | 20 years
Millers Branch Solar Development Phase 2 |  |
Business Acquisition [Line Items] |  |
Approximate nameplate capacity |  | 180
Life output of plant (in years) |  | 15 years
Millers Branch Solar Development Phase 3 |  |
Business Acquisition [Line Items] |  |
Approximate nameplate capacity |  | 90
Life output of plant (in years) |  | 15 years
Millers Branch Solar Development Phase 3 | Subsequent Event |  |
Business Acquisition [Line Items] |  |
Additional capacity | 42 |
Millers Branch Solar Development |  |
Business Acquisition [Line Items] |  |
Construction work in progress | $ |  | $ 159
Millers Branch Solar Development | Subsequent Event |  |
Business Acquisition [Line Items] |  |
Additional capacity | 512 |

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