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Regulatory Matters - GPC Nuclear Construction Cost and Schedule (Details) - GEORGIA POWER CO - USD ($) $ in Millions | 6 Months Ended | 12003 Months Ended
--- | --- | ---
Jun. 30, 2023 | Dec. 31, 2022
Loss Contingencies [Line Items] |  |
Pre-tax charge to income |  | $ 407
Plant Vogtle Units 3 And 4 |  |
Loss Contingencies [Line Items] |  |
Base project capital cost forecast | $ 10,576 |
Construction contingency estimate | 17 |
Total project capital cost forecast | 10,593 |
Net investment as of end of the period | (9,944) |
Remaining estimate to complete | 649 |
Estimated cost to complete, costs not shared with other owners | 610 |
Estimated cost to complete, construction monitoring costs approved for recovery | 33 |
Expected capitalized costs | 422 |
Capitalized interest accrued | 365 |
Plant Vogtle Units 3 And 4 | Twenty Fifth Vogtle Construction Monitoring Report |  |
Loss Contingencies [Line Items] |  |
Guarantor obligations | 1,700 |
Customer refund | $ 188 |

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