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CONTINGENCIES, COMMITMENTS, AND GUARANTEES - Commitments (Details) - Georgia Power - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
MEAG Power |  |  |
Loss Contingencies [Line Items] |  |  |
Percent ownership | 5.00% |  |
Plant Vogtle Units 1 and 2 |  |  |
Loss Contingencies [Line Items] |  |  |
Capacity payments | $ 3 | $ 4 | $ 6
Recorded Unconditional Purchase Obligation, Fiscal Year Maturity Schedule [Abstract] |  |  |
Total | 39 |  |
Recorded unconditional purchase obligation, year one | 4 |  |
Recorded unconditional purchase obligation, year two | 4 |  |
Recorded unconditional purchase obligation, year three | 2 |  |
Recorded unconditional purchase obligation, year four | 2 |  |
Recorded unconditional purchase obligation, year five | 2 |  |
Recorded unconditional purchase obligation, after year five | $ 25 |  |

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