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ACQUISITIONS AND DISPOSITIONS - Southern Power Narrative (Details) - SOUTHERN POWER CO $ in Millions | 1 Months Ended | 12 Months Ended
--- | --- | ---
Nov. 30, 2024 MW | Dec. 31, 2024 USD ($) MW | Dec. 31, 2023 USD ($)
Kay Wind Facility |  |  |
Asset Acquisition [Line Items] |  |  |
Approximate Nameplate Capacity (MW) | 299 |  |
PPA Contract Period | 20 years |  |
Nameplate Capacity, Amount Repowered | 200 |  |
South Cheyenne Solar Facility |  |  |
Asset Acquisition [Line Items] |  |  |
Approximate Nameplate Capacity (MW) |  | 150 |
PPA Contract Period |  | 20 years |
Millers Branch Solar Development Phase 1 |  |  |
Asset Acquisition [Line Items] |  |  |
Approximate Nameplate Capacity (MW) |  | 200 |
PPA Contract Period |  | 20 years |
Millers Branch Solar Development Phase 2 |  |  |
Asset Acquisition [Line Items] |  |  |
Approximate Nameplate Capacity (MW) |  | 180 |
PPA Contract Period |  | 15 years |
Millers Branch |  |  |
Asset Acquisition [Line Items] |  |  |
Cost of construction | $ |  | $ 292 |
South Cheyenne Solar Facility and Millers Branch Solar Development |  |  |
Asset Acquisition [Line Items] |  |  |
Payments to acquire businesses | $ |  |  | $ 193

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