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Regulatory Matters - GPC Nuclear Construction Regulatory Matters (Details) - GEORGIA POWER CO - USD ($) $ in Millions |  |  |  | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | --- | ---
May 01, 2024 | Apr. 29, 2024 | Aug. 01, 2023 | Sep. 30, 2024 | Jun. 30, 2024 | Sep. 30, 2024 | Dec. 31, 2023
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |
Return on equity reduction, negative impact on earnings |  |  |  |  | $ 10 |  |
Recovery of construction and capital costs |  |  |  | $ 10 |  |  |
Plant Vogtle Unit 3 |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |
Requested rate increase, annual amount |  |  | $ 318 |  |  |  |
Plant Vogtle Units 3 And 4 |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |
Regulatory asset amortization period |  |  |  | 10 years |  | 10 years |
Approved rate increase (decrease) |  | $ 5,462 |  |  |  | $ 2,100 |
Approved recovery of retail rate items |  |  |  |  |  | 362 |
Associated retail rate base items |  | $ 647 |  |  |  |  |
Requested rate increase (decrease) amount | $ 730 |  |  |  |  |  |
Requested revenues increase (decrease) percentage | 5.00% |  |  |  |  |  |
Return on equity reduction, negative impact on earnings |  |  |  |  | $ 80 |  | $ 310
Public utilities, approved return on equity percentage |  |  |  |  | 0.00% |  |
Plant Vogtle Units 3 And 4 | Deferred Income Tax Charge, Debt Component |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |
Remaining net book value |  |  |  | $ 24 |  | 24 |
Plant Vogtle Units 3 And 4 | Deferred Income Tax Charge |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |
Remaining net book value |  |  |  | 30 |  | 30 |
Plant Vogtle Units 3 And 4 | Deferred Income Tax Charge, Equity Component |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |
Remaining net book value |  |  |  | $ 40 |  | $ 40 |

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