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REGULATORY MATTERS - GPC Rate Plans and Integrated Resource Plan (Details) $ in Millions |  |  |  |  |  | 1 Months Ended | 3 Months Ended | 12 Months Ended | 56 Months Ended | 60 Months Ended |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Dec. 31, 2024 USD ($) agreement | Dec. 03, 2024 MW | Jun. 27, 2024 agreement | Jan. 12, 2024 MW | Oct. 27, 2023 MW | Jan. 31, 2025 MW | Jun. 30, 2023 USD ($) | May 31, 2023 USD ($) | Sep. 30, 2024 facility MW | Jun. 30, 2024 USD ($) | Dec. 31, 2028 MW | Dec. 31, 2025 USD ($) MW | Dec. 31, 2024 USD ($) MW | Dec. 31, 2023 USD ($) turbine MW | Dec. 31, 2022 USD ($) agreement MW | Dec. 31, 2019 | Dec. 31, 2028 MW | Dec. 31, 2028 MW | Mar. 31, 2023 USD ($)
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Regulatory asset amortization period | 4 years |  |  |  |  |  |  |  |  |  |  |  | 4 years |  |  |  |  |  |
Georgia Power |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Requested number of power purchase agreements to be certified | agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 6 |  |  |  |
Requested additional generating capacity (in MW) |  |  |  |  |  |  |  |  | 265 |  |  |  | 1,567 |  | 8,500 |  |  |  |
Requested number of affiliate power purchase agreements to be certified | agreement | 2 |  | 5 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Requested rate increase (decrease), amount | $ |  |  |  |  |  |  |  | $ 1,100 |  |  |  |  |  |  | $ 14,000 |  |  |  |
Requested recovery of construction costs | $ |  |  |  |  |  |  |  |  |  | $ 10 |  |  | $ 760 |  |  |  |  |  |
Public Utilities, Number Of Battery Energy Storage Facilities | facility |  |  |  |  |  |  |  |  | 4 |  |  |  |  |  |  |  |  |  |
Total certified amount | $ | $ 2,800 |  |  |  |  |  |  |  |  |  |  |  | $ 2,800 |  |  |  |  |  |
Georgia Power | SEGCO |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ownership percentage, equity method investment | 50.00% |  |  |  |  |  |  |  |  |  |  |  | 50.00% |  |  |  |  |  |
Georgia Power | Plant Scherer (coal) Unit 3 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percent Ownership | 75.00% |  |  |  |  |  |  |  |  |  |  |  | 75.00% |  |  |  |  |  |
Georgia Power | Plant Scherer (coal) Units 1 and 2 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percent Ownership | 8.40% |  |  |  |  |  |  |  |  |  |  |  | 8.40% |  |  |  |  |  |
Georgia Power | Plant Hatch Units 1 And 2 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percent Ownership | 50.10% |  |  |  |  |  |  |  |  |  |  |  | 50.10% |  |  |  |  |  |
Georgia Power | Plant Vogtle (nuclear) Units 1 and 2 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percent Ownership | 45.70% |  |  |  |  |  |  |  |  |  |  |  | 45.70% |  |  |  |  |  |
Georgia Power | ECCR |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Regulatory asset amortization period | 4 years |  |  |  |  |  |  |  |  |  |  |  | 4 years |  |  |  |  |  |
Approved rate decrease | $ |  |  |  |  |  |  |  |  |  |  |  |  | $ 60 | $ 20 |  |  |  |  |
Compliance costs expected to be incurred | $ |  |  |  |  |  |  |  |  |  |  |  |  | $ 265 | $ 300 |  |  |  |  |
Georgia Power | 2022 Alternate Rate Plan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Retail rate of return on common equity | 10.50% |  |  |  |  |  |  |  |  |  |  |  | 10.50% |  |  |  |  |  |
Equity rate of return on common equity | 56.00% |  |  |  |  |  |  |  |  |  |  |  | 56.00% |  |  |  |  |  |
Portion of actual earnings above approved ROE band refunded to customers |  |  |  |  |  |  |  |  |  |  |  |  | 40.00% |  |  |  |  |  |
Portion of actual earnings above approved ROE band applied to reduce regulatory assets |  |  |  |  |  |  |  |  |  |  |  |  | 40.00% |  |  |  |  |  |
Portion of actual earnings above approved ROE band retained by subsidiary company |  |  |  |  |  |  |  |  |  |  |  |  | 20.00% |  |  |  |  |  |
Georgia Power | 2019 Alternate Rate Plan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Retail rate of return on common equity |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 10.50% |  |  |
Portion of actual earnings above approved ROE band refunded to customers |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 40.00% |  |  |
Portion of actual earnings above approved ROE band applied to reduce regulatory assets |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 40.00% |  |  |
Portion of actual earnings above approved ROE band retained by subsidiary company |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 20.00% |  |  |
Customer refund liability in absence of base rate case | $ |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 117
Georgia Power | Scenario, Forecast |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Requested additional generating capacity (in MW) |  |  |  |  |  |  |  |  |  |  | 228 | 380 |  |  |  |  | 230 | 750 |
Georgia Power | Scenario, Forecast | ECCR |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Approved rate increase | $ |  |  |  |  |  |  |  |  |  |  |  | $ 123 |  |  |  |  |  |  |
Compliance costs expected to be incurred | $ |  |  |  |  |  |  |  |  |  |  |  | $ 330 |  |  |  |  |  |  |
Georgia Power | Subsequent Event |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Requested additional generating capacity (in MW) |  |  |  |  |  | 1,100 |  |  |  |  |  |  |  |  |  |  |  |  |
Georgia Power | Subsequent Event | SEGCO |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Requested additional generating capacity (in MW) |  |  |  |  |  | 500 |  |  |  |  |  |  |  |  |  |  |  |  |
Georgia Power | Subsequent Event | Plant Scherer (coal) Unit 3 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Requested additional generating capacity (in MW) |  |  |  |  |  | 614 |  |  |  |  |  |  |  |  |  |  |  |  |
Georgia Power | Subsequent Event | Plant Scherer Unit 3 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Requested additional generating capacity (in MW) |  |  |  |  |  | 187 |  |  |  |  |  |  |  |  |  |  |  |  |
Georgia Power | Subsequent Event | Plant Bowen Units 1 Through 4 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Requested additional generating capacity (in MW) |  |  |  |  |  | 3,160 |  |  |  |  |  |  |  |  |  |  |  |  |
Georgia Power | Subsequent Event | Plant Scherer (coal) Units 1 and 2 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Requested additional generating capacity (in MW) |  |  |  |  |  | 137 |  |  |  |  |  |  |  |  |  |  |  |  |
Georgia Power | Subsequent Event | Plant McIntosh Units 10 And 11 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Requested additional generating capacity (in MW) |  |  |  |  |  | 1,319 |  |  |  |  |  |  |  |  |  |  |  |  |
Addition to nameplate capacity |  |  |  |  |  | 194 |  |  |  |  |  |  |  |  |  |  |  |  |
Georgia Power | Subsequent Event | Plant McIntosh Units 1 Through 8 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Requested additional generating capacity (in MW) |  |  |  |  |  | 640 |  |  |  |  |  |  |  |  |  |  |  |  |
Addition to nameplate capacity |  |  |  |  |  | 74 |  |  |  |  |  |  |  |  |  |  |  |  |
Georgia Power | Subsequent Event | Plant Hatch Units 1 And 2 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Requested additional generating capacity (in MW) |  |  |  |  |  | 900 |  |  |  |  |  |  |  |  |  |  |  |  |
Georgia Power | Subsequent Event | Plant Vogtle (nuclear) Units 1 and 2 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Requested additional generating capacity (in MW) |  |  |  |  |  | 1,060 |  |  |  |  |  |  |  |  |  |  |  |  |
Addition to nameplate capacity |  |  |  |  |  | 112 |  |  |  |  |  |  |  |  |  |  |  |  |
Georgia Power | Subsequent Event | Plant Goat Rock Units 3 Through 6 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Addition to nameplate capacity |  |  |  |  |  | 16 |  |  |  |  |  |  |  |  |  |  |  |  |
Georgia Power | Plant Yates |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of turbines | turbine |  |  |  |  |  |  |  |  |  |  |  |  |  | 3 |  |  |  |  |
Approved additional generating capacity (in MW) |  |  |  | 442 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Georgia Power | Plant Bowen Units 1 and 2 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Approved additional generating capacity (in MW) |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,400 |  |  |  |  |
Georgia Power | Customer Refunds | 2019 Alternate Rate Plan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Portion of actual earnings above approved ROE band refunded to customers, value | $ |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 117
Alabama Power |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Requested rate increase (decrease), amount | $ |  |  |  |  |  |  | $ 78 |  |  |  |  |  |  |  |  |  |  |  |
Percent Ownership | 14.00% |  |  |  |  |  |  |  |  |  |  |  | 14.00% |  |  |  |  |  |
Alabama Power | SEGCO |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ownership percentage, equity method investment | 50.00% |  |  |  |  |  |  |  |  |  |  |  | 50.00% |  |  |  |  |  |
Alabama Power | Subsequent Event | SEGCO |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Requested additional generating capacity (in MW) |  |  |  |  |  | 500 |  |  |  |  |  |  |  |  |  |  |  |  |
Maximum | Georgia Power |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Requested additional generating capacity (in MW) |  | 500 |  |  | 500 |  |  |  | 500 |  |  |  |  |  |  |  |  |  |
Maximum | Georgia Power | 2022 Alternate Rate Plan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Retail rate of return on common equity | 11.90% |  |  |  |  |  |  |  |  |  |  |  | 11.90% |  |  |  |  |  |
Maximum | Georgia Power | 2019 Alternate Rate Plan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Retail rate of return on common equity |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 12.00% | 12.00% |  |  |
Maximum | Georgia Power | Subsequent Event |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Requested additional generating capacity (in MW) |  |  |  |  |  | 4,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Maximum | Georgia Power | Plant Yates |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Requested additional generating capacity (in MW) |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,400 |  |  |  |  |
Minimum | Georgia Power | 2022 Alternate Rate Plan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Retail rate of return on common equity | 9.50% |  |  |  |  |  |  |  |  |  |  |  | 9.50% |  |  |  |  |  |
Minimum | Georgia Power | 2019 Alternate Rate Plan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Retail rate of return on common equity |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 9.50% |  |  |

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