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Fair Value Measurements - Schedule of Assets and Liabilities Measured at Fair Value (Details) - USD ($) $ in Millions | Jun. 30, 2024 | Dec. 31, 2023
--- | --- | ---
Assets: |  |
Derivatives | $ 30 | $ 32
Liabilities: |  |
Derivatives | 642 | 659
Other | 22 |
Collateral already posted, assets, aggregate fair value | 24 |
Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Liabilities: |  |
Other | 0 |
Significant Other Observable Inputs (Level 2) |  |
Liabilities: |  |
Other | 13 |
Significant Unobservable Inputs (Level 3) |  |
Liabilities: |  |
Other | 9 |
ALABAMA POWER CO |  |
Assets: |  |
Derivatives | 9 | 5
Liabilities: |  |
Derivatives | 60 | 100
Collateral already posted, assets, aggregate fair value | 0 |
GEORGIA POWER CO |  |
Assets: |  |
Derivatives | 1 | 2
Liabilities: |  |
Derivatives | 65 | 113
MISSISSIPPI POWER CO |  |
Assets: |  |
Derivatives | 1 | 1
Liabilities: |  |
Derivatives | 32 | 47
SOUTHERN POWER CO |  |
Assets: |  |
Derivatives | 4 | 3
Liabilities: |  |
Derivatives | 33 | 27
Other | 22 |
SOUTHERN POWER CO | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Liabilities: |  |
Other | 0 |
SOUTHERN POWER CO | Significant Other Observable Inputs (Level 2) |  |
Liabilities: |  |
Other | 13 |
SOUTHERN POWER CO | Significant Unobservable Inputs (Level 3) |  |
Liabilities: |  |
Other | 9 |
SOUTHERN Co GAS |  |
Assets: |  |
Derivatives | 15 | 21
Liabilities: |  |
Derivatives | 97 | 87
Total |  |
Collateral already posted, assets, aggregate fair value | 24 | $ 62
Fair Value, Measurements, Recurring |  |
Assets: |  |
Cash equivalents and restricted cash | 464 |
Other investments | 41 |
Total | 3,136 |
Liabilities: |  |
Contingent consideration | 19 |
Total | 744 |
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Cash equivalents and restricted cash | 447 |
Other investments | 9 |
Total | 1,451 |
Liabilities: |  |
Contingent consideration | 3 |
Total | 20 |
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Cash equivalents and restricted cash | 17 |
Other investments | 24 |
Total | 1,490 |
Liabilities: |  |
Contingent consideration | 0 |
Total | 699 |
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Cash equivalents and restricted cash | 0 |
Other investments | 8 |
Total | 8 |
Liabilities: |  |
Contingent consideration | 16 |
Total | 25 |
Fair Value, Measurements, Recurring | Net Asset Value as a Practical Expedient (NAV) |  |
Assets: |  |
Total | 187 |
Fair Value, Measurements, Recurring | Energy-related derivatives |  |
Assets: |  |
Derivatives | 67 |
Liabilities: |  |
Derivatives | 230 |
Fair Value, Measurements, Recurring | Energy-related derivatives | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Derivatives | 5 |
Liabilities: |  |
Derivatives | 17 |
Fair Value, Measurements, Recurring | Energy-related derivatives | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Derivatives | 62 |
Liabilities: |  |
Derivatives | 213 |
Fair Value, Measurements, Recurring | Energy-related derivatives | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Derivatives | 0 |
Liabilities: |  |
Derivatives | 0 |
Fair Value, Measurements, Recurring | Interest rate derivatives |  |
Assets: |  |
Derivatives | 1 |
Liabilities: |  |
Derivatives | 295 |
Fair Value, Measurements, Recurring | Interest rate derivatives | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Derivatives | 0 |
Liabilities: |  |
Derivatives | 0 |
Fair Value, Measurements, Recurring | Interest rate derivatives | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Derivatives | 1 |
Liabilities: |  |
Derivatives | 295 |
Fair Value, Measurements, Recurring | Interest rate derivatives | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Derivatives | 0 |
Liabilities: |  |
Derivatives | 0 |
Fair Value, Measurements, Recurring | Domestic equity |  |
Assets: |  |
Investments in trusts | 1,039 |
Fair Value, Measurements, Recurring | Domestic equity | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Investments in trusts | 794 |
Fair Value, Measurements, Recurring | Domestic equity | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Investments in trusts | 245 |
Fair Value, Measurements, Recurring | Domestic equity | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Investments in trusts | 0 |
Fair Value, Measurements, Recurring | Foreign equity |  |
Assets: |  |
Investments in trusts | 335 |
Fair Value, Measurements, Recurring | Foreign equity | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Investments in trusts | 155 |
Fair Value, Measurements, Recurring | Foreign equity | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Investments in trusts | 180 |
Fair Value, Measurements, Recurring | Foreign equity | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Investments in trusts | 0 |
Fair Value, Measurements, Recurring | U.S. Treasury and government agency securities |  |
Assets: |  |
Investments in trusts | 362 |
Fair Value, Measurements, Recurring | U.S. Treasury and government agency securities | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Investments in trusts | 0 |
Fair Value, Measurements, Recurring | U.S. Treasury and government agency securities | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Investments in trusts | 362 |
Fair Value, Measurements, Recurring | U.S. Treasury and government agency securities | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Investments in trusts | 0 |
Fair Value, Measurements, Recurring | Municipal bonds |  |
Assets: |  |
Investments in trusts | 48 |
Fair Value, Measurements, Recurring | Municipal bonds | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Investments in trusts | 0 |
Fair Value, Measurements, Recurring | Municipal bonds | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Investments in trusts | 48 |
Fair Value, Measurements, Recurring | Municipal bonds | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Investments in trusts | 0 |
Fair Value, Measurements, Recurring | Pooled funds – fixed income |  |
Assets: |  |
Investments in trusts | 7 |
Fair Value, Measurements, Recurring | Pooled funds – fixed income | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Investments in trusts | 0 |
Fair Value, Measurements, Recurring | Pooled funds – fixed income | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Investments in trusts | 7 |
Fair Value, Measurements, Recurring | Pooled funds – fixed income | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Investments in trusts | 0 |
Fair Value, Measurements, Recurring | Corporate bonds |  |
Assets: |  |
Investments in trusts | 434 |
Fair Value, Measurements, Recurring | Corporate bonds | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Investments in trusts | 0 |
Fair Value, Measurements, Recurring | Corporate bonds | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Investments in trusts | 434 |
Fair Value, Measurements, Recurring | Corporate bonds | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Investments in trusts | 0 |
Fair Value, Measurements, Recurring | Mortgage and asset backed securities |  |
Assets: |  |
Investments in trusts | 106 |
Fair Value, Measurements, Recurring | Mortgage and asset backed securities | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Investments in trusts | 0 |
Fair Value, Measurements, Recurring | Mortgage and asset backed securities | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Investments in trusts | 106 |
Fair Value, Measurements, Recurring | Mortgage and asset backed securities | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Investments in trusts | 0 |
Fair Value, Measurements, Recurring | Private equity |  |
Assets: |  |
Investments in trusts | 178 |
Fair Value, Measurements, Recurring | Private equity | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Investments in trusts | 0 |
Fair Value, Measurements, Recurring | Private equity | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Investments in trusts | 0 |
Fair Value, Measurements, Recurring | Private equity | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Investments in trusts | 0 |
Fair Value, Measurements, Recurring | Private equity | Net Asset Value as a Practical Expedient (NAV) |  |
Assets: |  |
Investments in trusts | 178 |
Fair Value, Measurements, Recurring | Cash and cash equivalents |  |
Assets: |  |
Investments in trusts | 1 |
Fair Value, Measurements, Recurring | Cash and cash equivalents | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Investments in trusts | 1 |
Fair Value, Measurements, Recurring | Cash and cash equivalents | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Investments in trusts | 0 |
Fair Value, Measurements, Recurring | Cash and cash equivalents | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Investments in trusts | 0 |
Fair Value, Measurements, Recurring | Other |  |
Assets: |  |
Investments in trusts | 53 |
Fair Value, Measurements, Recurring | Other | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Investments in trusts | 40 |
Fair Value, Measurements, Recurring | Other | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Investments in trusts | 4 |
Fair Value, Measurements, Recurring | Other | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Investments in trusts | 0 |
Fair Value, Measurements, Recurring | Other | Net Asset Value as a Practical Expedient (NAV) |  |
Assets: |  |
Investments in trusts | 9 |
Fair Value, Measurements, Recurring | Foreign currency derivatives |  |
Liabilities: |  |
Derivatives | 178 |
Fair Value, Measurements, Recurring | Foreign currency derivatives | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Liabilities: |  |
Derivatives | 0 |
Fair Value, Measurements, Recurring | Foreign currency derivatives | Significant Other Observable Inputs (Level 2) |  |
Liabilities: |  |
Derivatives | 178 |
Fair Value, Measurements, Recurring | Foreign currency derivatives | Significant Unobservable Inputs (Level 3) |  |
Liabilities: |  |
Derivatives | 0 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO |  |
Assets: |  |
Cash equivalents and restricted cash | 30 |
Other investments | 24 |
Total | 1,415 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Cash equivalents and restricted cash | 13 |
Other investments | 0 |
Total | 609 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Cash equivalents and restricted cash | 17 |
Other investments | 24 |
Total | 619 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Cash equivalents and restricted cash | 0 |
Other investments | 0 |
Total | 0 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Net Asset Value as a Practical Expedient (NAV) |  |
Assets: |  |
Total | 187 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Energy-related derivatives |  |
Assets: |  |
Derivatives | 22 |
Liabilities: |  |
Derivatives | 73 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Energy-related derivatives | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Derivatives | 0 |
Liabilities: |  |
Derivatives | 0 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Energy-related derivatives | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Derivatives | 22 |
Liabilities: |  |
Derivatives | 73 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Energy-related derivatives | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Derivatives | 0 |
Liabilities: |  |
Derivatives | 0 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Domestic equity |  |
Assets: |  |
Investments in trusts | 670 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Domestic equity | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Investments in trusts | 433 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Domestic equity | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Investments in trusts | 237 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Domestic equity | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Investments in trusts | 0 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Foreign equity |  |
Assets: |  |
Investments in trusts | 155 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Foreign equity | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Investments in trusts | 155 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Foreign equity | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Investments in trusts | 0 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Foreign equity | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Investments in trusts | 0 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | U.S. Treasury and government agency securities |  |
Assets: |  |
Investments in trusts | 22 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | U.S. Treasury and government agency securities | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Investments in trusts | 0 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | U.S. Treasury and government agency securities | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Investments in trusts | 22 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | U.S. Treasury and government agency securities | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Investments in trusts | 0 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Municipal bonds |  |
Assets: |  |
Investments in trusts | 1 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Municipal bonds | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Investments in trusts | 0 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Municipal bonds | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Investments in trusts | 1 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Municipal bonds | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Investments in trusts | 0 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Corporate bonds |  |
Assets: |  |
Investments in trusts | 267 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Corporate bonds | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Investments in trusts | 0 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Corporate bonds | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Investments in trusts | 267 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Corporate bonds | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Investments in trusts | 0 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Mortgage and asset backed securities |  |
Assets: |  |
Investments in trusts | 28 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Mortgage and asset backed securities | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Investments in trusts | 0 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Mortgage and asset backed securities | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Investments in trusts | 28 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Mortgage and asset backed securities | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Investments in trusts | 0 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Private equity |  |
Assets: |  |
Investments in trusts | 178 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Private equity | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Investments in trusts | 0 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Private equity | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Investments in trusts | 0 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Private equity | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Investments in trusts | 0 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Private equity | Net Asset Value as a Practical Expedient (NAV) |  |
Assets: |  |
Investments in trusts | 178 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Other |  |
Assets: |  |
Investments in trusts | 18 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Other | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Investments in trusts | 8 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Other | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Investments in trusts | 1 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Other | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Investments in trusts | 0 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Other | Net Asset Value as a Practical Expedient (NAV) |  |
Assets: |  |
Investments in trusts | 9 |
Fair Value, Measurements, Recurring | GEORGIA POWER CO |  |
Assets: |  |
Total | 1,222 |
Fair Value, Measurements, Recurring | GEORGIA POWER CO | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Total | 393 |
Fair Value, Measurements, Recurring | GEORGIA POWER CO | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Total | 829 |
Fair Value, Measurements, Recurring | GEORGIA POWER CO | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Total | 0 |
Fair Value, Measurements, Recurring | GEORGIA POWER CO | Energy-related derivatives |  |
Assets: |  |
Derivatives | 14 |
Liabilities: |  |
Derivatives | 78 |
Fair Value, Measurements, Recurring | GEORGIA POWER CO | Energy-related derivatives | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Derivatives | 0 |
Liabilities: |  |
Derivatives | 0 |
Fair Value, Measurements, Recurring | GEORGIA POWER CO | Energy-related derivatives | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Derivatives | 14 |
Liabilities: |  |
Derivatives | 78 |
Fair Value, Measurements, Recurring | GEORGIA POWER CO | Energy-related derivatives | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Derivatives | 0 |
Liabilities: |  |
Derivatives | 0 |
Fair Value, Measurements, Recurring | GEORGIA POWER CO | Domestic equity |  |
Assets: |  |
Investments in trusts | 362 |
Fair Value, Measurements, Recurring | GEORGIA POWER CO | Domestic equity | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Investments in trusts | 361 |
Fair Value, Measurements, Recurring | GEORGIA POWER CO | Domestic equity | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Investments in trusts | 1 |
Fair Value, Measurements, Recurring | GEORGIA POWER CO | Domestic equity | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Investments in trusts | 0 |
Fair Value, Measurements, Recurring | GEORGIA POWER CO | Foreign equity |  |
Assets: |  |
Investments in trusts | 179 |
Fair Value, Measurements, Recurring | GEORGIA POWER CO | Foreign equity | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Investments in trusts | 0 |
Fair Value, Measurements, Recurring | GEORGIA POWER CO | Foreign equity | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Investments in trusts | 179 |
Fair Value, Measurements, Recurring | GEORGIA POWER CO | Foreign equity | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Investments in trusts | 0 |
Fair Value, Measurements, Recurring | GEORGIA POWER CO | U.S. Treasury and government agency securities |  |
Assets: |  |
Investments in trusts | 340 |
Fair Value, Measurements, Recurring | GEORGIA POWER CO | U.S. Treasury and government agency securities | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Investments in trusts | 0 |
Fair Value, Measurements, Recurring | GEORGIA POWER CO | U.S. Treasury and government agency securities | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Investments in trusts | 340 |
Fair Value, Measurements, Recurring | GEORGIA POWER CO | U.S. Treasury and government agency securities | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Investments in trusts | 0 |
Fair Value, Measurements, Recurring | GEORGIA POWER CO | Municipal bonds |  |
Assets: |  |
Investments in trusts | 47 |
Fair Value, Measurements, Recurring | GEORGIA POWER CO | Municipal bonds | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Investments in trusts | 0 |
Fair Value, Measurements, Recurring | GEORGIA POWER CO | Municipal bonds | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Investments in trusts | 47 |
Fair Value, Measurements, Recurring | GEORGIA POWER CO | Municipal bonds | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Investments in trusts | 0 |
Fair Value, Measurements, Recurring | GEORGIA POWER CO | Corporate bonds |  |
Assets: |  |
Investments in trusts | 167 |
Fair Value, Measurements, Recurring | GEORGIA POWER CO | Corporate bonds | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Investments in trusts | 0 |
Fair Value, Measurements, Recurring | GEORGIA POWER CO | Corporate bonds | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Investments in trusts | 167 |
Fair Value, Measurements, Recurring | GEORGIA POWER CO | Corporate bonds | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Investments in trusts | 0 |
Fair Value, Measurements, Recurring | GEORGIA POWER CO | Mortgage and asset backed securities |  |
Assets: |  |
Investments in trusts | 78 |
Fair Value, Measurements, Recurring | GEORGIA POWER CO | Mortgage and asset backed securities | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Investments in trusts | 0 |
Fair Value, Measurements, Recurring | GEORGIA POWER CO | Mortgage and asset backed securities | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Investments in trusts | 78 |
Fair Value, Measurements, Recurring | GEORGIA POWER CO | Mortgage and asset backed securities | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Investments in trusts | 0 |
Fair Value, Measurements, Recurring | GEORGIA POWER CO | Other |  |
Assets: |  |
Investments in trusts | 35 |
Fair Value, Measurements, Recurring | GEORGIA POWER CO | Other | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Investments in trusts | 32 |
Fair Value, Measurements, Recurring | GEORGIA POWER CO | Other | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Investments in trusts | 3 |
Fair Value, Measurements, Recurring | GEORGIA POWER CO | Other | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Investments in trusts | 0 |
Fair Value, Measurements, Recurring | MISSISSIPPI POWER CO | Energy-related derivatives |  |
Assets: |  |
Derivatives | 16 |
Liabilities: |  |
Derivatives | 47 |
Fair Value, Measurements, Recurring | MISSISSIPPI POWER CO | Energy-related derivatives | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Derivatives | 0 |
Liabilities: |  |
Derivatives | 0 |
Fair Value, Measurements, Recurring | MISSISSIPPI POWER CO | Energy-related derivatives | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Derivatives | 16 |
Liabilities: |  |
Derivatives | 47 |
Fair Value, Measurements, Recurring | MISSISSIPPI POWER CO | Energy-related derivatives | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Derivatives | 0 |
Liabilities: |  |
Derivatives | 0 |
Fair Value, Measurements, Recurring | SOUTHERN POWER CO |  |
Liabilities: |  |
Contingent consideration | 19 |
Total | 74 |
Fair Value, Measurements, Recurring | SOUTHERN POWER CO | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Liabilities: |  |
Contingent consideration | 3 |
Total | 3 |
Fair Value, Measurements, Recurring | SOUTHERN POWER CO | Significant Other Observable Inputs (Level 2) |  |
Liabilities: |  |
Contingent consideration | 0 |
Total | 46 |
Fair Value, Measurements, Recurring | SOUTHERN POWER CO | Significant Unobservable Inputs (Level 3) |  |
Liabilities: |  |
Contingent consideration | 16 |
Total | 25 |
Fair Value, Measurements, Recurring | SOUTHERN POWER CO | Energy-related derivatives |  |
Assets: |  |
Derivatives | 4 |
Liabilities: |  |
Derivatives | 3 |
Fair Value, Measurements, Recurring | SOUTHERN POWER CO | Energy-related derivatives | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Derivatives | 0 |
Liabilities: |  |
Derivatives | 0 |
Fair Value, Measurements, Recurring | SOUTHERN POWER CO | Energy-related derivatives | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Derivatives | 4 |
Liabilities: |  |
Derivatives | 3 |
Fair Value, Measurements, Recurring | SOUTHERN POWER CO | Energy-related derivatives | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Derivatives | 0 |
Liabilities: |  |
Derivatives | 0 |
Fair Value, Measurements, Recurring | SOUTHERN POWER CO | Foreign currency derivatives |  |
Liabilities: |  |
Derivatives | 30 |
Fair Value, Measurements, Recurring | SOUTHERN POWER CO | Foreign currency derivatives | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Liabilities: |  |
Derivatives | 0 |
Fair Value, Measurements, Recurring | SOUTHERN POWER CO | Foreign currency derivatives | Significant Other Observable Inputs (Level 2) |  |
Liabilities: |  |
Derivatives | 30 |
Fair Value, Measurements, Recurring | SOUTHERN POWER CO | Foreign currency derivatives | Significant Unobservable Inputs (Level 3) |  |
Liabilities: |  |
Derivatives | 0 |
Fair Value, Measurements, Recurring | SOUTHERN Co GAS |  |
Assets: |  |
Total | 28 |
Liabilities: |  |
Total | 118 |
Fair Value, Measurements, Recurring | SOUTHERN Co GAS | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Total | 6 |
Liabilities: |  |
Total | 17 |
Fair Value, Measurements, Recurring | SOUTHERN Co GAS | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Total | 22 |
Liabilities: |  |
Total | 101 |
Fair Value, Measurements, Recurring | SOUTHERN Co GAS | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Total | 0 |
Liabilities: |  |
Total | 0 |
Fair Value, Measurements, Recurring | SOUTHERN Co GAS | Energy-related derivatives |  |
Assets: |  |
Derivatives | 11 |
Liabilities: |  |
Derivatives | 29 |
Fair Value, Measurements, Recurring | SOUTHERN Co GAS | Energy-related derivatives | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Derivatives | 5 |
Liabilities: |  |
Derivatives | 17 |
Fair Value, Measurements, Recurring | SOUTHERN Co GAS | Energy-related derivatives | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Derivatives | 6 |
Liabilities: |  |
Derivatives | 12 |
Fair Value, Measurements, Recurring | SOUTHERN Co GAS | Energy-related derivatives | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Derivatives | 0 |
Liabilities: |  |
Derivatives | 0 |
Fair Value, Measurements, Recurring | SOUTHERN Co GAS | Interest rate derivatives |  |
Assets: |  |
Derivatives | 1 |
Liabilities: |  |
Derivatives | 89 |
Fair Value, Measurements, Recurring | SOUTHERN Co GAS | Interest rate derivatives | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Derivatives | 0 |
Liabilities: |  |
Derivatives | 0 |
Fair Value, Measurements, Recurring | SOUTHERN Co GAS | Interest rate derivatives | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Derivatives | 1 |
Liabilities: |  |
Derivatives | 89 |
Fair Value, Measurements, Recurring | SOUTHERN Co GAS | Interest rate derivatives | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Derivatives | 0 |
Liabilities: |  |
Derivatives | 0 |
Fair Value, Measurements, Recurring | SOUTHERN Co GAS | Domestic equity |  |
Assets: |  |
Non-qualified deferred compensation trusts | 7 |
Fair Value, Measurements, Recurring | SOUTHERN Co GAS | Domestic equity | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Non-qualified deferred compensation trusts | 0 |
Fair Value, Measurements, Recurring | SOUTHERN Co GAS | Domestic equity | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Non-qualified deferred compensation trusts | 7 |
Fair Value, Measurements, Recurring | SOUTHERN Co GAS | Domestic equity | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Non-qualified deferred compensation trusts | 0 |
Fair Value, Measurements, Recurring | SOUTHERN Co GAS | Foreign equity |  |
Assets: |  |
Non-qualified deferred compensation trusts | 1 |
Fair Value, Measurements, Recurring | SOUTHERN Co GAS | Foreign equity | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Non-qualified deferred compensation trusts | 0 |
Fair Value, Measurements, Recurring | SOUTHERN Co GAS | Foreign equity | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Non-qualified deferred compensation trusts | 1 |
Fair Value, Measurements, Recurring | SOUTHERN Co GAS | Foreign equity | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Non-qualified deferred compensation trusts | 0 |
Fair Value, Measurements, Recurring | SOUTHERN Co GAS | Pooled funds – fixed income |  |
Assets: |  |
Non-qualified deferred compensation trusts | 7 |
Fair Value, Measurements, Recurring | SOUTHERN Co GAS | Pooled funds – fixed income | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Non-qualified deferred compensation trusts | 0 |
Fair Value, Measurements, Recurring | SOUTHERN Co GAS | Pooled funds – fixed income | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Non-qualified deferred compensation trusts | 0 |
Fair Value, Measurements, Recurring | SOUTHERN Co GAS | Cash and cash equivalents |  |
Assets: |  |
Non-qualified deferred compensation trusts | 1 |
Fair Value, Measurements, Recurring | SOUTHERN Co GAS | Cash and cash equivalents | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Non-qualified deferred compensation trusts | 1 |
Fair Value, Measurements, Recurring | SOUTHERN Co GAS | Cash and cash equivalents | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Non-qualified deferred compensation trusts | 0 |
Fair Value, Measurements, Recurring | SOUTHERN Co GAS | Cash and cash equivalents | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Non-qualified deferred compensation trusts | $ 0 |

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