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Regulatory Matters - GPC Nuclear Construction (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2024 | Jun. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2024 | Sep. 30, 2023
Loss Contingencies [Line Items] |  |  |  |  |
Credit on plant vogtle units 3 and 4 | $ 0 |  | $ (160) | $ 21 | $ (160)
GEORGIA POWER CO |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |
Credit on plant vogtle units 3 and 4 | 0 | $ 21 | (160) | 21 | (160)
After tax credit on plant vogtle units 3 and 4 |  | $ 16 | $ (120) | 16 | $ (120)
GEORGIA POWER CO | Plant Vogtle Units 3 And 4 |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |
Estimated cost to complete, construction contingency estimate, financing costs | 3,530 |  |  | 3,530 |
Costs recovered to date | $ 3,080 |  |  | $ 3,080 |

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