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REGULATORY MATTERS - GPC Regulatory Matters (Details) - USD ($) $ in Millions |  |  | 1 Months Ended | 3 Months Ended | 12 Months Ended | 192 Months Ended
--- | --- | --- | --- | --- | --- | ---
May 01, 2024 | Aug. 01, 2023 | Apr. 30, 2024 | May 31, 2023 | Dec. 31, 2022 | Jun. 30, 2024 | Dec. 31, 2023 | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2009 | Dec. 31, 2024
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Net regulatory assets |  |  |  |  |  |  | $ 6,523.0 | $ 7,041.0 | $ 6,523.0 |  |  |  | $ 7,041.0
Regulatory asset amortization period |  |  |  |  |  |  |  | 4 years |  |  |  |  | 4 years
Deferred Income Tax Charges |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Net regulatory assets |  |  |  |  |  |  | 897.0 | $ 927.0 | 897.0 |  |  |  | $ 927.0
Georgia Power |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Requested recovery of construction costs |  |  |  |  |  | $ 10.0 |  | 760.0 |  |  |  |  |
Requested rate increase (decrease), amount |  |  |  | $ 1,100.0 |  |  |  |  |  | $ 14,000.0 |  |  |
Net regulatory assets |  |  |  |  |  |  | 5,090.0 | 6,139.0 | 5,090.0 |  |  |  | 6,139.0
Pre-tax charge to income |  |  |  |  |  | 7.6 |  |  | 567.0 |  |  |  |
After tax charge to income |  |  |  |  |  | 5.7 |  |  | 424.0 |  |  |  |
Requested rate increase (decrease), percentage |  |  |  | 54.00% |  |  |  |  |  |  |  |  |
Georgia Power | Deferred Income Tax Charges |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Net regulatory assets |  |  |  |  |  |  | 605.0 | $ 634.0 | 605.0 |  |  |  | 634.0
Plant Vogtle Units 3 and 4 | Georgia Power |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Estimated in-service capital cost |  |  |  |  |  |  |  |  |  |  |  | $ 4,418.0 |
Proceeds from recovery of financing costs |  |  |  |  |  |  |  |  |  |  |  |  | $ 3,080.0
Requested recovery of construction costs |  |  |  |  |  |  |  |  |  |  |  | 7,562.0 |
Increase (decrease) in tariff |  |  |  |  | $ 36.0 |  |  |  |  |  |  |  |
Public utilities, approved rate increase (decrease), amount |  |  |  |  |  |  |  |  |  |  | $ 2,100.0 | 5,462.0 |
Requested rate increase (decrease), amount |  |  |  |  |  |  |  |  |  |  |  | 730.0 |
Regulatory asset amortization period |  |  |  |  |  |  |  | 10 years |  |  |  |  | 10 years
Requested recovery of rate base items |  |  |  |  |  |  |  |  |  |  |  | 1,020.0 |
Approved recovery of retail base rate |  |  |  |  |  |  |  |  |  |  | 362.0 |  |
Requested recovery of remaining retail rate base items |  |  |  |  |  |  |  |  |  |  |  | $ 647.0 |
Return on equity reduction, negative impact on earnings |  |  | $ 10.0 |  |  | $ 80.0 |  |  | $ 310.0 | $ 300.0 |  |  |
Pre-tax charge to income |  |  |  |  |  |  | 228.0 |  |  |  |  |  |
After tax charge to income |  |  |  |  |  |  | $ 170.0 |  |  |  |  |  |
Authorized ROE |  |  |  |  |  | 0.00% |  |  |  |  |  |  |
Requested rate increase (decrease), percentage | 5.00% |  |  |  |  |  |  |  |  |  |  |  |
Plant Vogtle Units 3 and 4 | Georgia Power | Deferred Income Tax Charge, Debt Component |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Net regulatory assets |  |  |  |  |  |  |  | $ 23.0 |  |  |  |  | $ 23.0
Plant Vogtle Units 3 and 4 | Georgia Power | Deferred Income Tax Charges |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Net regulatory assets |  |  |  |  |  |  |  | $ 29.0 |  |  |  |  | $ 29.0
Regulatory asset amortization period |  |  |  |  |  |  |  | 10 years |  |  |  |  | 10 years
Plant Vogtle Units 3 and 4 | Georgia Power | Deferred Income Tax Charge, Equity Component |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Net regulatory assets |  |  |  |  |  |  |  | $ 39.0 |  |  |  |  | $ 39.0
Plant Vogtle Units 3 and 4 | Georgia Power |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Public utilities, approved rate increase (decrease), amount |  |  |  |  |  |  |  |  |  |  | 2,100.0 |  |
Requested rate increase (decrease), amount |  |  |  |  |  |  |  |  |  |  | $ 3,600.0 |  |
Requested rate increase, annual amount |  | $ 318.0 |  |  |  |  |  |  |  |  |  |  |

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