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Regulatory Matters - GPC Rate Plans and Integrated Resource Plan (Details) $ in Millions |  |  |  |  | 1 Months Ended | 3 Months Ended | 9 Months Ended | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Jun. 27, 2024 MW | Apr. 24, 2024 USD ($) | Apr. 16, 2024 MW | Jan. 12, 2024 turbine MW | Sep. 30, 2024 USD ($) | Sep. 30, 2024 USD ($) facility MW | Sep. 30, 2024 USD ($) | Dec. 31, 2028 MW | Dec. 31, 2025 MW | Oct. 01, 2024 USD ($) | Mar. 07, 2024 USD ($) | Dec. 31, 2023 USD ($)
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Regulatory asset balance related to storm damage |  |  |  |  |  |  |  |  |  |  |  | $ 66
GEORGIA POWER CO |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Requested additional generating capacity (in MWs) | MW | 1,258 |  |  |  |  | 265 |  |  |  |  |  |
Number of turbines | turbine |  |  |  | 3 |  |  |  |  |  |  |  |
Number of battery energy storage facilities | facility |  |  |  |  |  | 4 |  |  |  |  |  |
Damage costs recovered annually |  |  |  |  |  |  | $ 31 |  |  |  |  |
Weather-related damages |  |  |  |  | $ 1,100 |  |  |  |  |  |  |
Regulatory asset balance related to storm damage |  |  |  |  | $ 1,200 | $ 1,200 | $ 1,200 |  |  |  |  |
GEORGIA POWER CO | Traditional Base | Subsequent Event |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Requested rate increase (decrease), amount, due in next fiscal year |  |  |  |  |  |  |  |  |  | $ 194 |  |
GEORGIA POWER CO | Traditional Base, Georgia State | Subsequent Event |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Requested rate increase (decrease), amount, due in next fiscal year |  |  |  |  |  |  |  |  |  | 122 |  |
GEORGIA POWER CO | Environmental Compliance Cost Recovery, Traditional | Subsequent Event |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Requested rate increase (decrease), amount, due in next fiscal year |  |  |  |  |  |  |  |  |  | 126 |  |
GEORGIA POWER CO | Demand Side-Management | Subsequent Event |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Requested rate increase (decrease), amount, due in next fiscal year |  |  |  |  |  |  |  |  |  | (22) |  |
GEORGIA POWER CO | Municipal Franchise Fee | Subsequent Event |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Requested rate increase (decrease), amount, due in next fiscal year |  |  |  |  |  |  |  |  |  | $ 9 |  |
GEORGIA POWER CO | Scenario, Forecast |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Requested additional generating capacity (in MWs) | MW |  |  |  |  |  |  |  | 228 | 380 |  |  |
GEORGIA POWER CO | Maximum |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Requested additional generating capacity (in MWs) | MW |  |  | 500 |  |  | 500 |  |  |  |  |  |
GEORGIA POWER CO | Plant Yates | Maximum |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Requested additional generating capacity (in MWs) | MW |  |  | 1,400 | 442 |  |  |  |  |  |  |  |
GEORGIA POWER CO | Affiliate PPA |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Requested additional generating capacity (in MWs) | MW |  |  | 750 |  |  |  |  |  |  |  |  |
GEORGIA POWER CO | Non-Affiliate PPA |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Requested additional generating capacity (in MWs) | MW |  |  | 230 |  |  |  |  |  |  |  |  |
Southern Co and Georgia Power | Disposal Group, Held-for-sale, Not Discontinued Operations |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Assets held for sale |  |  |  |  |  |  |  |  |  |  | $ 236 |
Proceeds from sale of transmission assets |  | $ 351 |  |  |  |  |  |  |  |  |  |
Gain (loss) on sale |  |  |  |  |  | $ 114 |  |  |  |  |  |
Gain (loss) on sale, after tax |  |  |  |  |  | $ 84 |  |  |  |  |  |

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