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ASSET RETIREMENT OBLIGATIONS - Estimated Costs of Decommissioning (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2021 USD ($)
Alabama Power | Plant Farley |
Public Utilities, General Disclosures [Line Items] |
Decommissioning periods: Beginning year | 2037
Decommissioning periods: Completion year | 2076
Site study costs | $ 1,720
Alabama Power | Radiated structures | Plant Farley |
Public Utilities, General Disclosures [Line Items] |
Site study costs | 1,234
Alabama Power | Spent fuel management | Plant Farley |
Public Utilities, General Disclosures [Line Items] |
Site study costs | 387
Alabama Power | Non-radiated structures | Plant Farley |
Public Utilities, General Disclosures [Line Items] |
Site study costs | $ 99
Georgia Power | Plant Hatch |
Public Utilities, General Disclosures [Line Items] |
Decommissioning periods: Beginning year | 2034
Decommissioning periods: Completion year | 2075
Site study costs | $ 1,018
Georgia Power | Plant Vogtle Units 1 and 2 |
Public Utilities, General Disclosures [Line Items] |
Decommissioning periods: Beginning year | 2047
Decommissioning periods: Completion year | 2079
Site study costs | $ 883
Georgia Power | Radiated structures | Plant Hatch |
Public Utilities, General Disclosures [Line Items] |
Site study costs | 771
Georgia Power | Radiated structures | Plant Vogtle Units 1 and 2 |
Public Utilities, General Disclosures [Line Items] |
Site study costs | 628
Georgia Power | Spent fuel management | Plant Hatch |
Public Utilities, General Disclosures [Line Items] |
Site study costs | 186
Georgia Power | Spent fuel management | Plant Vogtle Units 1 and 2 |
Public Utilities, General Disclosures [Line Items] |
Site study costs | 170
Georgia Power | Non-radiated structures | Plant Hatch |
Public Utilities, General Disclosures [Line Items] |
Site study costs | 61
Georgia Power | Non-radiated structures | Plant Vogtle Units 1 and 2 |
Public Utilities, General Disclosures [Line Items] |
Site study costs | $ 85

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