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REGULATORY MATTERS - GPC Schedule of Nuclear Construction Cost and Schedule (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2023 | Sep. 30, 2023 | Dec. 31, 2022 | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Commitments [Line Items] |  |  |  |  |  |
Total AFUDC and interest capitalized |  |  |  | $ 400 | $ 327 | $ 282
Georgia Power |  |  |  |  |  |
Commitments [Line Items] |  |  |  |  |  |
Pre-tax charge to income |  | $ 160 | $ 407 | 567 |  |
Total AFUDC and interest capitalized |  |  |  | 251 | $ 213 | $ 190
Georgia Power | Plant Vogtle Units 3 and 4 |  |  |  |  |  |
Commitments [Line Items] |  |  |  |  |  |
Base project capital cost forecast | $ 10,717 |  |  | 10,717 |  |
Construction contingency estimate | 36 |  |  | 36 |  |
Preliminary estimated cost to complete | 10,753 |  |  | 10,753 |  |
Net investment | (10,564) |  |  | (10,564) |  |
Remaining estimate to complete | 189 |  |  | 189 |  |
Estimated cost to complete, costs not shared with other owners | 610 |  |  | 610 |  |
Estimated cost to complete, construction monitoring costs approved for recovery | 33 |  |  | 33 |  |
Pre-tax charge to income | 228 |  |  |  |  |
Total AFUDC and interest capitalized |  |  |  | 440 |  |
Total AFUDC and interest capitalized, accrual amount | $ 417 |  |  | $ 417 |  |

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