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ACQUISITIONS AND DISPOSITIONS - Alabama Power Narrative (Details) - USD ($) $ in Millions | 1 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2022 | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Business Acquisition [Line Items] |  |  |  |
Capital expenditures related to qualifying projects |  | $ 9,095 | $ 7,923 | $ 7,586
Alabama Power |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Capital expenditures related to qualifying projects |  | $ 2,022 | $ 2,016 | $ 1,753
Alabama Power | Calhoun Generating Station |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Purchase price | $ 179 |  |  |
Capital expenditures related to qualifying projects | $ 171 |  |  |

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