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ACQUISITIONS AND DISPOSITIONS - Alabama Power Narrative (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Business Acquisition [Line Items] |  |  |
Capital expenditures related to qualifying projects | $ 8,955 | $ 9,095 | $ 7,923
Alabama Power |  |  |
Business Acquisition [Line Items] |  |  |
Capital expenditures related to qualifying projects | $ 1,881 | $ 2,022 | 2,016
Alabama Power | Calhoun Generating Station |  |  |
Business Acquisition [Line Items] |  |  |
Purchase price |  |  | 179
Capital expenditures related to qualifying projects |  |  | $ 171

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