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FINANCING - DOE Loan Guarantee Borrowings (Details) - USD ($) | 12 Months Ended
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Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2019
Debt Instrument [Line Items] |  |  |  |
Remaining borrowing capacity | $ 7,566,000,000 |  |  |
Line of credit facility, maximum borrowing capacity | 7,605,000,000 |  |  |
Georgia Power |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Percent of eligible project costs (may not exceed) |  |  |  | 70.00%
Remaining borrowing capacity | 1,726,000,000 |  |  |
Principal amortization payments | 86,000,000 | $ 88,000,000 | $ 96,000,000 |
Line of credit facility, maximum borrowing capacity | $ 1,750,000,000 |  |  |
Basis spread on variable rate | 0.375% |  |  |
Amortization period | 5 years |  |  |
FFB Credit Facility | Georgia Power |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Eligible project costs to be reimbursed |  |  |  | $ 5,130,000,000
Funds received under guarantee settlement agreement, less customer refunds |  |  |  | $ 1,492,000,000
Remaining borrowing capacity |  |  | $ 0 |
Principal amortization payments | $ 86,000,000 |  |  |
Line of credit facility, maximum borrowing capacity | $ 4,800,000,000 | $ 4,900,000,000 |  |
Plant Vogtle Units 3 and 4 | Georgia Power |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Ownership interest percentage required for voting for continuing construction | 90.00% |  |  |

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