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Fair Value Measurements - Schedule of Assets and Liabilities Measured at Fair Value (Details) - USD ($) $ in Millions | Jun. 30, 2023 | Dec. 31, 2022
--- | --- | ---
Assets: |  |
Derivatives | $ 57 | $ 141
Liabilities: |  |
Derivatives | 693 | 617
Other | 13 |
Collateral already posted, assets, aggregate fair value | 52 |
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 | 0 |
ALABAMA POWER CO |  |
Assets: |  |
Derivatives | 12 | 38
Liabilities: |  |
Derivatives | 64 | 15
Collateral already posted, assets, aggregate fair value | 0 |
GEORGIA POWER CO |  |
Assets: |  |
Derivatives | 5 | 21
Investments in trusts | 25 |
Liabilities: |  |
Derivatives | 90 | 41
MISSISSIPPI POWER CO |  |
Assets: |  |
Derivatives | 8 | 42
Liabilities: |  |
Derivatives | 36 | 15
SOUTHERN POWER CO |  |
Assets: |  |
Derivatives | 3 | 8
Liabilities: |  |
Derivatives | 37 | 59
Other | 13 |
Collateral already posted, assets, aggregate fair value | 15 |
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 | 0 |
SOUTHERN Co GAS |  |
Assets: |  |
Derivatives | 31 | 28
Liabilities: |  |
Derivatives | 110 | 110
Total |  |
Collateral already posted, assets, aggregate fair value | 52 | $ 41
Fair Value, Measurements, Recurring |  |
Assets: |  |
Cash equivalents | 1,506 |
Other investments | 51 |
Total | 3,966 |
Liabilities: |  |
Contingent consideration | 12 |
Total | 810 |
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Cash equivalents | 1,494 |
Other investments | 9 |
Total | 2,401 |
Liabilities: |  |
Contingent consideration | 0 |
Total | 33 |
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Cash equivalents | 12 |
Other investments | 34 |
Total | 1,382 |
Liabilities: |  |
Contingent consideration | 0 |
Total | 765 |
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Cash equivalents | 0 |
Other investments | 8 |
Total | 8 |
Liabilities: |  |
Contingent consideration | 12 |
Total | 12 |
Fair Value, Measurements, Recurring | Net Asset Value as a Practical Expedient (NAV) |  |
Assets: |  |
Total | 175 |
Fair Value, Measurements, Recurring | Energy-related derivatives |  |
Assets: |  |
Derivatives | 93 |
Liabilities: |  |
Derivatives | 311 |
Fair Value, Measurements, Recurring | Energy-related derivatives | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Derivatives | 7 |
Liabilities: |  |
Derivatives | 33 |
Fair Value, Measurements, Recurring | Energy-related derivatives | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Derivatives | 86 |
Liabilities: |  |
Derivatives | 278 |
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 | 4 |
Liabilities: |  |
Derivatives | 304 |
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 | 4 |
Liabilities: |  |
Derivatives | 304 |
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 | 923 |
Fair Value, Measurements, Recurring | Domestic equity | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Investments in trusts | 718 |
Fair Value, Measurements, Recurring | Domestic equity | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Investments in trusts | 205 |
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 | 307 |
Fair Value, Measurements, Recurring | Foreign equity | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Investments in trusts | 140 |
Fair Value, Measurements, Recurring | Foreign equity | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Investments in trusts | 167 |
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 | 333 |
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 | 333 |
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 | 46 |
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 | 46 |
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 | 391 |
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 | 391 |
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 | 90 |
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 | 90 |
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 | 166 |
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 | 166 |
Fair Value, Measurements, Recurring | Cash and cash equivalents |  |
Assets: |  |
Investments in trusts | 2 |
Fair Value, Measurements, Recurring | Cash and cash equivalents | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Investments in trusts | 2 |
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 | 47 |
Fair Value, Measurements, Recurring | Other | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Investments in trusts | 31 |
Fair Value, Measurements, Recurring | Other | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Investments in trusts | 7 |
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 | 170 |
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 | 170 |
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 | 122 |
Other investments | 34 |
Total | 1,391 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Cash equivalents | 110 |
Other investments | 0 |
Total | 677 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Cash equivalents | 12 |
Other investments | 34 |
Total | 539 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Cash equivalents | 0 |
Other investments | 0 |
Total | 0 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Net Asset Value as a Practical Expedient (NAV) |  |
Assets: |  |
Total | 175 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Energy-related derivatives |  |
Assets: |  |
Derivatives | 32 |
Liabilities: |  |
Derivatives | 84 |
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 | 32 |
Liabilities: |  |
Derivatives | 84 |
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 | 618 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Domestic equity | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Investments in trusts | 420 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Domestic equity | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Investments in trusts | 198 |
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 | 140 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Foreign equity | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Investments in trusts | 140 |
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 | 20 |
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 | 20 |
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 | 221 |
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 | 221 |
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 | 21 |
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 | 21 |
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 | 166 |
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 | 166 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Other |  |
Assets: |  |
Investments in trusts | 16 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Other | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Investments in trusts | 7 |
Fair Value, Measurements, Recurring | ALABAMA POWER CO | Other | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Investments in trusts | 0 |
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 | 1,110 |
Fair Value, Measurements, Recurring | GEORGIA POWER CO | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Total | 322 |
Fair Value, Measurements, Recurring | GEORGIA POWER CO | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Total | 788 |
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 | 17 |
Liabilities: |  |
Derivatives | 102 |
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 | 17 |
Liabilities: |  |
Derivatives | 102 |
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 | 299 |
Fair Value, Measurements, Recurring | GEORGIA POWER CO | Domestic equity | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Investments in trusts | 298 |
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 | 166 |
Fair Value, Measurements, Recurring | GEORGIA POWER CO | Foreign equity | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Investments in trusts |  |
Fair Value, Measurements, Recurring | GEORGIA POWER CO | Foreign equity | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Investments in trusts | 166 |
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 | 313 |
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 | 313 |
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 | 45 |
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 | 45 |
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 | 170 |
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 | 170 |
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 | 69 |
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 | 69 |
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 | 31 |
Fair Value, Measurements, Recurring | GEORGIA POWER CO | Other | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Investments in trusts | 24 |
Fair Value, Measurements, Recurring | GEORGIA POWER CO | Other | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Investments in trusts | 7 |
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 | 27 |
Liabilities: |  |
Derivatives | 55 |
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 | 27 |
Liabilities: |  |
Derivatives | 55 |
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 |  |
Assets: |  |
Cash equivalents | 5 |
Total | 9 |
Liabilities: |  |
Contingent consideration | 12 |
Total | 63 |
Fair Value, Measurements, Recurring | SOUTHERN POWER CO | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Cash equivalents | 5 |
Total | 5 |
Liabilities: |  |
Contingent consideration | 0 |
Total | 0 |
Fair Value, Measurements, Recurring | SOUTHERN POWER CO | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Cash equivalents | 0 |
Total | 4 |
Liabilities: |  |
Contingent consideration | 0 |
Total | 51 |
Fair Value, Measurements, Recurring | SOUTHERN POWER CO | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Cash equivalents | 0 |
Total | 0 |
Liabilities: |  |
Contingent consideration | 12 |
Total | 12 |
Fair Value, Measurements, Recurring | SOUTHERN POWER CO | Energy-related derivatives |  |
Assets: |  |
Derivatives | 4 |
Liabilities: |  |
Derivatives | 10 |
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 | 10 |
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 | 28 |
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 | 28 |
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: |  |
Cash equivalents | 215 |
Total | 248 |
Liabilities: |  |
Total | 148 |
Fair Value, Measurements, Recurring | SOUTHERN Co GAS | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Cash equivalents | 215 |
Total | 224 |
Liabilities: |  |
Total | 33 |
Fair Value, Measurements, Recurring | SOUTHERN Co GAS | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Cash equivalents | 0 |
Total | 24 |
Liabilities: |  |
Total | 115 |
Fair Value, Measurements, Recurring | SOUTHERN Co GAS | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Cash equivalents | 0 |
Total | 0 |
Liabilities: |  |
Total | 0 |
Fair Value, Measurements, Recurring | SOUTHERN Co GAS | Energy-related derivatives |  |
Assets: |  |
Derivatives | 13 |
Liabilities: |  |
Derivatives | 60 |
Fair Value, Measurements, Recurring | SOUTHERN Co GAS | Energy-related derivatives | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Derivatives | 7 |
Liabilities: |  |
Derivatives | 33 |
Fair Value, Measurements, Recurring | SOUTHERN Co GAS | Energy-related derivatives | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Derivatives | 6 |
Liabilities: |  |
Derivatives | 27 |
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 | 4 |
Liabilities: |  |
Derivatives | 88 |
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 | 4 |
Liabilities: |  |
Derivatives | 88 |
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 | 6 |
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 | 6 |
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 Other Observable Inputs (Level 2) |  |
Assets: |  |
Non-qualified deferred compensation trusts | 7 |
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 equivalents |  |
Assets: |  |
Non-qualified deferred compensation trusts | 2 |
Fair Value, Measurements, Recurring | SOUTHERN Co GAS | Cash equivalents | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Non-qualified deferred compensation trusts | 2 |
Fair Value, Measurements, Recurring | SOUTHERN Co GAS | Cash equivalents | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Non-qualified deferred compensation trusts | 0 |
Fair Value, Measurements, Recurring | SOUTHERN Co GAS | Cash equivalents | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Non-qualified deferred compensation trusts | $ 0 |

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