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REGULATORY MATTERS - GPC Rate Plans, Integrated Resource Plan and COVID-19 Costs (Details) $ in Millions |  |  |  |  |  |  |  |  | 1 Months Ended | 3 Months Ended | 12 Months Ended | 60 Months Ended | 68 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Mar. 24, 2024 USD ($) | Jan. 12, 2024 turbine MW | Jan. 01, 2024 MW | Oct. 27, 2023 MW | Aug. 30, 2023 USD ($) | Aug. 01, 2023 USD ($) | May 16, 2023 USD ($) | Jan. 01, 2022 USD ($) | Dec. 31, 2022 USD ($) | Aug. 31, 2022 USD ($) | Jul. 31, 2022 agreement | Nov. 30, 2021 USD ($) | Dec. 31, 2023 USD ($) | Sep. 30, 2023 USD ($) | Dec. 31, 2022 USD ($) | Dec. 31, 2028 MW | Dec. 31, 2025 USD ($) MW | Dec. 31, 2024 USD ($) | Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($) | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2009 USD ($) | Dec. 31, 2028 MW | Dec. 31, 2028 MW | Oct. 06, 2023 pump | Mar. 31, 2023 USD ($) | Jan. 31, 2018 USD ($) | Dec. 31, 2016
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Regulatory asset amortization period |  |  |  |  |  |  |  |  |  |  |  |  | 4 years |  |  |  |  |  | 4 years |  |  |  |  |  |  |  |  |  |  |
Net regulatory assets |  |  |  |  |  |  |  |  | $ 5,833 |  |  |  | $ 6,523 |  | $ 5,833 |  |  |  | $ 6,523 | $ 5,833 |  |  |  |  |  |  |  |  |  |
Customer Refunds |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net regulatory assets |  |  |  |  |  |  |  |  | (183) |  |  |  | (19) |  | (183) |  |  |  | (19) | (183) |  |  |  |  |  |  |  |  |  |
Georgia Power |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Approved rate decrease |  |  |  |  |  |  |  | $ 10 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public utilities, approved rate increase (decrease), amount |  |  |  |  |  |  |  |  |  |  |  | $ 252 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Requested rate increase (decrease), amount |  |  |  |  |  |  | $ 1,100 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net regulatory assets |  |  |  |  |  |  |  |  | 4,663 |  |  |  | $ 5,090 |  | 4,663 |  |  |  | 5,090 | 4,663 |  |  |  |  |  |  |  |  |  |
Requested number of power purchase agreements to be certified | agreement |  |  |  |  |  |  |  |  |  |  | 6 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Requested number of affiliate power purchase agreements to be certified | agreement |  |  |  |  |  |  |  |  |  |  | 5 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Requested rate increase (decrease), percentage |  |  |  |  |  |  | 54.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Pre-tax charge to income |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 160 | 407 |  |  |  | $ 567 |  |  |  |  |  |  |  |  |  |  |
After tax charge to income |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 120 | 304 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Georgia Power | Plant Scherer (coal) Unit 3 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percent Ownership |  |  |  |  |  |  |  |  |  |  |  |  | 75.00% |  |  |  |  |  | 75.00% |  |  |  |  |  |  |  |  |  |  |
Approved additional generating capacity (in MW) | MW |  |  |  | 614 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Georgia Power | Plant Gaston Units 1 through 4 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percent Ownership |  |  |  |  |  |  |  |  |  |  |  |  | 50.00% |  |  |  |  |  | 50.00% |  |  |  |  |  |  |  |  |  |  |
Approved additional generating capacity (in MW) | MW |  |  |  | 500 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Georgia Power | ECCR |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Regulatory asset amortization period |  |  |  |  |  |  |  |  |  |  |  |  | 4 years |  |  |  |  |  | 4 years |  |  |  |  |  |  |  |  |  |  |
Approved rate decrease |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 20 |  |  |  |  |  |  |  |  |  |  |
Compliance costs expected to be incurred |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 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 applied to reduce regulatory assets |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 40.00% |  |  |  |  |  |  |  |  |  |  |
Portion of actual earnings above approved ROE band refunded to customers |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 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 applied to reduce regulatory assets |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 40.00% |  |  |  |  |  |  |
Portion of actual earnings above approved ROE band refunded to customers |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 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 |  |  |  |  |  |  |  |  | 5 |  |  |  |  |  | 5 |  |  |  |  | 5 |  |  |  |  |  |  |  | $ 117 |  |
Georgia Power | Scenario, Forecast |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Requested additional generating capacity (in MW) | MW |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 750 | 230 |  |  |  |
Georgia Power | Scenario, Forecast | ECCR |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Approved rate decrease |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 60 |  |  |  |  |  |  |  |  |  |  |  |
Compliance costs expected to be incurred |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 330 | 305 |  |  |  |  |  |  |  |  |  |  |  |
Georgia Power | Scenario, Forecast | Subsequent Event |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Requested additional generating capacity (in MW) | MW |  |  | 1,567 |  |  |  |  |  |  |  |  |  |  |  |  | 228 | 380 |  |  |  |  |  |  |  |  |  |  |  |  |
Georgia Power | Plant Vogtle Units 3 and 4 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public utilities, approved rate increase (decrease), amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 2,100 |  |  |  |  |  |  |  |  |
Requested rate increase (decrease), amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 3,600 |  |  |  |  |  |  |  |  |
Requested rate increase, annual amount |  |  |  |  |  | $ 318 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Georgia Power | Plant Vogtle Units 3 and 4 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Retail rate of return on common equity |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 10.95%
Public utilities, approved rate increase (decrease), amount |  |  |  |  | $ 5,462 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2,100 |  |  |  |  |  |  |  |  |
Requested rate increase (decrease), amount |  |  |  |  | 729 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Decrease in tariff |  |  |  |  |  |  |  |  | (36) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Requested recovery of construction costs |  |  |  |  | 7,562 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Requested recovery of rate base items |  |  |  |  | 1,020 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Project capital cost forecast |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 7,300 |
Estimated in-service capital cost |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 4,418 |  |  |  |  |  |
Approved recovery of retail base rate |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 362 |  |  |  |  |  |  |  |  |
Requested recovery of remaining retail rate base items |  |  |  |  | $ 656 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Return on equity reduction, negative impact on earnings |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 310 | 300 | $ 270 |  |  |  |  |  |  |  |  |
Requested rate increase (decrease), percentage |  |  |  |  | 5.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Pre-tax charge to income |  |  |  |  |  |  |  |  |  |  |  |  | $ 228 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
After tax charge to income |  |  |  |  |  |  |  |  |  |  |  |  | $ 170 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percent Ownership |  |  |  |  |  |  |  |  |  |  |  |  | 45.70% |  |  |  |  |  | 45.70% |  |  |  |  |  |  |  |  |  |  |
Georgia Power | Plant Vogtle Units 3 and 4 | Seventeenth Vogtle Construction Monitoring Report |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Requested recovery of construction costs |  |  |  |  | $ 8,826 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Requested recovery of rate base items |  |  |  |  | $ 1,070 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Georgia Power | Plant Vogtle Units 3 and 4 | Scenario, Forecast |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Return on equity reduction, negative impact on earnings | $ 30 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 90 |  |  |  |  |  |  |  |  |  |  |  |
Georgia Power | Plant Yates | Subsequent Event |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of turbines | turbine |  | 3 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Approved additional generating capacity (in MW) | MW |  | 442 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Georgia Power | Plant Vogtle Unit 4 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of RCP's | pump |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1 |  |  |
Georgia Power | Plant Bowen Units 1 and 2 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Approved additional generating capacity (in MW) | MW |  |  |  | 1,400 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Georgia Power | Plant Tugalo |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Planned expenses to modernize plant |  |  |  |  |  |  |  |  |  | $ 115 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Georgia Power | Customer Refunds |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net regulatory assets |  |  |  |  |  |  |  |  | (121) |  |  |  | $ (4) |  | (121) |  |  |  | $ (4) | (121) |  |  |  |  |  |  |  |  |  |
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 |  |  |  |  |  |  |  |  | 5 |  |  |  |  |  | 5 |  |  |  |  | 5 |  |  |  |  |  |  |  | $ 117 |  |
Remaining Net Book Value of Retired Assets |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net regulatory assets |  |  |  |  |  |  |  |  | 1,543 |  |  |  | 1,357 |  | 1,543 |  |  |  | 1,357 | 1,543 |  |  |  |  |  |  |  |  |  |
Remaining Net Book Value of Retired Assets | Georgia Power |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net regulatory assets |  |  |  |  |  |  |  |  | $ 962 |  |  |  | 841 |  | $ 962 |  |  |  | 841 | $ 962 |  |  |  |  |  |  |  |  |  |
Remaining Net Book Value of Retired Assets | Georgia Power | Plant Wansley Units 1 and 2 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net regulatory assets |  |  |  |  |  |  |  |  |  |  |  |  | $ 488 |  |  |  |  |  | $ 488 |  |  |  |  |  |  |  |  |  |  |
Maximum | Georgia Power |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public utilities, approved rate increase (decrease), amount |  |  |  |  |  |  | $ 200 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Requested additional generating capacity (in MW) | MW |  |  |  | 1,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
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% |  |  |  |  | 12.00% | 12.00% |  | 12.00% |  |  |  |  |  |  |
Maximum | Georgia Power | Plant Vogtle Units 3 and 4 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of RCP's | pump |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 7 |  |  |
Maximum | Georgia Power | Plant Yates |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Requested additional generating capacity (in MW) | MW |  |  |  | 1,400 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Maximum | Georgia Power | Plant Vogtle Unit 4 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of RCP's | pump |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 4 |  |  |
Maximum | Remaining Net Book Value of Retired Assets | Georgia Power |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Regulatory asset amortization period |  |  |  |  |  |  |  |  | 3 years |  |  |  |  |  | 3 years |  |  |  |  | 3 years |  | 4 years |  |  |  |  |  |  |  |
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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