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REGULATORY MATTERS - GPC Transmission Asset Sales, Fuel Cost, and Storm Damage Recovery (Details) - USD ($) $ in Millions |  |  | 1 Months Ended | 3 Months Ended | 12 Months Ended | 24 Months Ended |
--- | --- | --- | --- | --- | --- | --- | ---
Apr. 24, 2024 | Jan. 01, 2023 | Sep. 30, 2024 | May 31, 2023 | Jun. 30, 2024 | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2022 | Mar. 07, 2024
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |
To be recovered amount |  |  |  | $ 2,200 |  |  |  |  |  |
Regulatory liabilities |  |  |  |  |  | $ 705 |  |  |  |
Regulatory asset |  |  |  |  |  |  | $ 66 | $ 216 | $ 216 |
Public utilities, property, plant and equipment, net |  |  |  |  |  | 104,689 | 99,844 |  |  |
Deferred amount to be billed in 2025 |  |  |  |  |  | 476 | 533 |  |  |
Other operations and maintenance |  |  |  |  |  | 6,539 | 6,093 | 6,824 |  |
Major storms |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |
Storm damage reserves |  |  |  |  |  |  |  | 239 |  |
Georgia Power |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |
Requested rate increase (decrease), amount |  |  |  | $ 1,100 |  |  |  | 14,000 |  |
Requested rate increase (decrease), percentage |  |  |  | 54.00% |  |  |  |  |  |
Recovery period |  |  |  | 3 years |  |  |  |  |  |
Over (under) recovered fuel balance |  |  |  |  |  | $ (1,200) | (1,900) |  |  |
Required period for options and hedges |  |  |  |  |  | 36 months |  |  |  |
Storm damage reserves |  | $ 31 |  |  |  |  |  |  | 213 |
Regulatory liabilities |  |  |  |  |  | $ 827 | 54 |  |  |
Regulatory asset |  |  |  |  |  |  |  | 83 | $ 83 |
Public utilities, property, plant and equipment, net |  |  |  |  |  | 44,038 | 40,995 |  |  |
Deferred amount to be billed in 2025 |  |  |  |  |  | 262 | 305 |  |  |
Other operations and maintenance |  |  |  |  |  | 2,372 | 2,083 | 2,349 |  |
Georgia Power | Major storms |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |
Storm damage reserves |  |  |  |  |  |  |  | $ 213 |  |
Weather related damages |  |  | $ 870 |  |  |  |  |  |  |
Regulatory asset |  |  |  |  |  | 750 |  |  |  |
Public utilities, property, plant and equipment, net |  |  |  |  |  | 90 |  |  |  |
Deferred amount to be billed in 2025 |  |  |  |  |  | 30 |  |  |  |
Georgia Power | Under Recovered Fuel Clause Revenues |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |
Over (under) recovered fuel balance |  |  |  |  |  | (713) | (694) |  |  |
Georgia Power | Deferred Under Recovered Fuel Clause Revenues |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |
Over (under) recovered fuel balance |  |  |  |  |  | (453) | (1,200) |  |  |
Georgia Power | Other regulatory assets, current |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |
Regulatory liabilities |  |  |  |  |  | 31 | 31 |  |  |
Georgia Power | Other Regulatory Assets |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |
Regulatory liabilities |  |  |  |  |  | $ 795 | $ 23 |  |  |
Georgia Power | Maximum |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |
Approved rate increase, percent |  |  |  | 40.00% |  |  |  |  |  |
Public utilities, approved rate increase (decrease), amount |  |  |  | $ 200 |  |  |  |  |  |
Southern Company And Georgia Power | Disposal Group, Held-for-sale, Not Discontinued Operations |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |
Net book value |  |  |  |  |  |  |  |  |  | $ 236
Purchase price | $ 351 |  |  |  |  |  |  |  |  |
Gain on sale |  |  |  |  | $ 114 |  |  |  |  |
Gain on sale, after tax |  |  |  |  | $ 84 |  |  |  |  |

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