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Acquisitions and Dispositions (Details) $ in Millions | 6 Months Ended |
--- | --- | ---
Jun. 30, 2024 USD ($) MW | Dec. 31, 2023 USD ($)
Business Acquisition [Line Items] |  |
Construction work in progress | $ | $ 5,231 | $ 7,784
SOUTHERN POWER CO |  |
Business Acquisition [Line Items] |  |
Construction work in progress | $ | $ 134 | $ 278
SOUTHERN POWER CO | 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 |
SOUTHERN POWER CO | Millers Branch Solar Development |  |
Business Acquisition [Line Items] |  |
Construction work in progress | $ | $ 117 |
SOUTHERN POWER CO | Millers Branch Solar Development Phase 1 |  |
Business Acquisition [Line Items] |  |
Approximate nameplate capacity | 200 |
Life output of plant (in years) | 20 years |
SOUTHERN POWER CO | Millers Branch Solar Development Phase 2 |  |
Business Acquisition [Line Items] |  |
Approximate nameplate capacity | 180 |
Life output of plant (in years) | 15 years |
SOUTHERN POWER CO | Millers Branch Solar Development Phase 3 |  |
Business Acquisition [Line Items] |  |
Approximate nameplate capacity | 90 |
Life output of plant (in years) | 15 years |
SOUTHERN POWER CO | Maximum | Millers Branch Solar Development |  |
Business Acquisition [Line Items] |  |
Approximate nameplate capacity | 500 |

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