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Income Taxes (Details) - USD ($) $ in Millions | 9 Months Ended |
--- | --- | ---
Sep. 30, 2024 | Sep. 30, 2023 | Dec. 31, 2023
Income Tax Contingency [Line Items] |  |  |
Effective tax (benefit) rate | 19.00% | 13.90% |
Unrecognized tax positions | $ 73 |  | $ 116
ALABAMA POWER CO |  |  |
Income Tax Contingency [Line Items] |  |  |
Effective tax (benefit) rate | 21.20% | 8.30% |
GEORGIA POWER CO |  |  |
Income Tax Contingency [Line Items] |  |  |
Effective tax (benefit) rate | 18.70% | 18.20% |
Unrecognized tax positions | $ 34 |  | $ 77
MISSISSIPPI POWER CO |  |  |
Income Tax Contingency [Line Items] |  |  |
Effective tax (benefit) rate | 20.00% | 16.90% |

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- Details
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