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REGULATORY MATTERS - GPC Fuel Cost and Storm Damage Recovery (Details) - USD ($) $ in Millions |  |  | 1 Months Ended | 6 Months Ended | 12 Months Ended | 24 Months Ended
--- | --- | --- | --- | --- | --- | ---
May 16, 2023 | Jan. 01, 2023 | Nov. 30, 2021 | Dec. 31, 2021 | Dec. 31, 2023 | Dec. 31, 2022
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |
To be recovered amount | $ 2,200 |  |  |  |  |
Net regulatory assets |  |  |  |  | $ 6,523 | $ 5,833
Georgia Power |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |
Public utilities, approved rate increase (decrease), amount |  |  | $ 252 |  |  |
Adjustment to fuel cost recovery rate if under recovered fuel balance exceeds budget thereafter |  |  |  | $ 200 |  |
Recovery period | 3 years |  |  |  |  |
Approved rate increase, percent |  |  | 15.00% |  |  |
Over (under) recovered fuel balance |  |  |  |  | $ (1,900) | (2,100)
Required period for options and hedges |  |  |  |  | 36 months |
Storm damage reserves |  | $ 31 |  |  |  | 213
Regulatory liabilities |  |  |  |  | $ 54 | 83
Net regulatory assets |  |  |  |  | 5,090 | $ 4,663
Requested rate increase (decrease), percentage | 54.00% |  |  |  |  |
Requested rate increase (decrease), amount | $ 1,100 |  |  |  |  |
Georgia Power | Under Recovered Fuel Clause Revenues |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |
Over (under) recovered fuel balance |  |  |  |  | (694) |
Georgia Power | Deferred Under Recovered Fuel Clause Revenues |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |
Over (under) recovered fuel balance |  |  |  |  | (1,200) |
Georgia Power | Other regulatory assets, current |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |
Regulatory liabilities |  |  |  |  | 31 |
Georgia Power | Other Regulatory Assets |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |
Regulatory liabilities |  |  |  |  | $ 23 |
Georgia Power | Maximum |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |
Public utilities, approved rate increase (decrease), amount | $ 200 |  |  |  |  |
Approved rate increase, percent | 40.00% |  |  |  |  |

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