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ASSET RETIREMENT OBLIGATIONS - Accumulated Provisions for the External Decommissioning Trust Funds (Details) - External decommissioning trust funds - USD ($) $ in Millions | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Georgia Power |  |
Public Utilities, General Disclosures [Line Items] |  |
Accumulated provisions for decommissioning | $ 1,163 | $ 1,018
Plant Farley | Alabama Power |  |
Public Utilities, General Disclosures [Line Items] |  |
Accumulated provisions for decommissioning | 1,259 | 1,125
Plant Hatch | Georgia Power |  |
Public Utilities, General Disclosures [Line Items] |  |
Accumulated provisions for decommissioning | 705 | 628
Plant Vogtle Units 1 and 2 | Georgia Power |  |
Public Utilities, General Disclosures [Line Items] |  |
Accumulated provisions for decommissioning | 434 | 382
Plant Vogtle Units 3 and 4 | Georgia Power |  |
Public Utilities, General Disclosures [Line Items] |  |
Accumulated provisions for decommissioning | $ 24 | $ 8

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- Definition Accumulated Provisions for Decommissioning. + References No definition available. + Details
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