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FAIR VALUE MEASUREMENTS - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Assets: |  |
Derivative asset | $ 45 | $ 32
Liabilities: |  |
Derivative liability | 554 | 659
Collateral already posted, aggregate fair value | 17 | 62
Recurring |  |
Assets: |  |
Cash equivalents and restricted cash | 552 | 268
Other investments | 48 | 44
Total | 3,349 | 2,806
Liabilities: |  |
Contingent consideration | 19 | 19
Other | 24 |
Total | 659 | 776
Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Cash equivalents and restricted cash | 533 | 253
Other investments | 9 | 9
Total | 1,594 | 1,238
Liabilities: |  |
Contingent consideration | 3 | 3
Other | 0 |
Total | 8 | 49
Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Cash equivalents and restricted cash | 19 | 15
Other investments | 31 | 27
Total | 1,557 | 1,382
Liabilities: |  |
Contingent consideration | 0 | 0
Other | 13 |
Total | 624 | 711
Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Cash equivalents and restricted cash | 0 | 0
Other investments | 8 | 8
Total | 8 | 8
Liabilities: |  |
Contingent consideration | 16 | 16
Other | 11 |
Total | 27 | 16
Recurring | Fair Value Measured at Net Asset Value Per Share (NAV) |  |
Assets: |  |
Total | 190 | 178
Alabama Power |  |
Assets: |  |
Derivative asset | 7 | 5
Liabilities: |  |
Derivative liability | 23 | 100
Collateral already posted, aggregate fair value | 0 |
Alabama Power | Recurring |  |
Assets: |  |
Cash equivalents and restricted cash | 353 | 134
Other investments | 31 | 27
Total | 1,795 | 1,435
Alabama Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Cash equivalents and restricted cash | 334 | 119
Other investments | 0 | 0
Total | 952 | 715
Alabama Power | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Cash equivalents and restricted cash | 19 | 15
Other investments | 31 | 27
Total | 653 | 542
Alabama Power | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Cash equivalents and restricted cash | 0 | 0
Other investments | 0 | 0
Total | 0 | 0
Alabama Power | Recurring | Fair Value Measured at Net Asset Value Per Share (NAV) |  |
Assets: |  |
Total | 190 | 178
Georgia Power |  |
Assets: |  |
Derivative asset | 4 | 2
Liabilities: |  |
Derivative liability | 27 | 113
Georgia Power | Recurring |  |
Assets: |  |
Cash equivalents and restricted cash | 35 |
Total | 1,290 | 1,176
Georgia Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Cash equivalents and restricted cash | 35 |
Total | 453 | 371
Georgia Power | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Cash equivalents and restricted cash | 0 |
Total | 837 | 805
Georgia Power | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Cash equivalents and restricted cash | 0 |
Total | 0 | 0
Mississippi Power |  |
Assets: |  |
Derivative asset | 2 | 1
Liabilities: |  |
Derivative liability | 17 | 47
Mississippi Power | Recurring |  |
Assets: |  |
Cash equivalents and restricted cash |  | 17
Total |  | 32
Mississippi Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Cash equivalents and restricted cash |  | 17
Total |  | 17
Mississippi Power | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Cash equivalents and restricted cash |  | 0
Total |  | 15
Mississippi Power | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Cash equivalents and restricted cash |  | 0
Total |  | 0
Southern Power |  |
Assets: |  |
Derivative asset | 4 | 3
Liabilities: |  |
Derivative liability | 51 | 27
Other |  | 13
Collateral already posted, aggregate fair value | 0 |
Southern Power | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Liabilities: |  |
Other |  | 0
Southern Power | Significant Other Observable Inputs (Level 2) |  |
Liabilities: |  |
Other |  | 13
Southern Power | Significant Unobservable Inputs (Level 3) |  |
Liabilities: |  |
Other |  | 0
Southern Power | Recurring |  |
Assets: |  |
Cash equivalents and restricted cash | 51 |
Total | 55 |
Liabilities: |  |
Contingent consideration | 19 |
Other | 24 |
Total | 94 | 59
Southern Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Cash equivalents and restricted cash | 51 |
Total | 51 |
Liabilities: |  |
Contingent consideration | 3 |
Other | 0 |
Total | 3 | 3
Southern Power | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Cash equivalents and restricted cash | 0 |
Total | 4 |
Liabilities: |  |
Contingent consideration | 0 |
Other | 13 |
Total | 64 | 40
Southern Power | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Cash equivalents and restricted cash | 0 |
Total | 0 |
Liabilities: |  |
Contingent consideration | 16 |
Other | 11 |
Total | 27 | 16
Southern Company Gas |  |
Assets: |  |
Derivative asset | 28 | 21
Liabilities: |  |
Derivative liability | 84 | 87
Collateral already posted, aggregate fair value | 17 | 62
Southern Company Gas | Recurring |  |
Assets: |  |
Cash equivalents and restricted cash | 22 |
Total | 82 | 26
Liabilities: |  |
Total | 95 | 137
Southern Company Gas | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Cash equivalents and restricted cash | 22 |
Total | 38 | 9
Liabilities: |  |
Total | 5 | 46
Southern Company Gas | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Cash equivalents and restricted cash | 0 |
Total | 44 | 17
Liabilities: |  |
Total | 90 | 91
Southern Company Gas | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Cash equivalents and restricted cash | 0 |
Total | 0 | 0
Liabilities: |  |
Total | 0 | 0
Energy-related derivatives | Recurring |  |
Assets: |  |
Derivative asset | 89 | 55
Liabilities: |  |
Derivative liability | 129 | 358
Energy-related derivatives | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Derivative asset | 12 | 6
Liabilities: |  |
Derivative liability | 5 | 46
Energy-related derivatives | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Derivative asset | 77 | 49
Liabilities: |  |
Derivative liability | 124 | 312
Energy-related derivatives | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Derivative asset | 0 | 0
Liabilities: |  |
Derivative liability | 0 | 0
Energy-related derivatives | Alabama Power | Recurring |  |
Assets: |  |
Derivative asset | 26 | 15
Liabilities: |  |
Derivative liability | 42 | 110
Energy-related derivatives | Alabama Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Derivative asset | 0 | 0
Liabilities: |  |
Derivative liability | 0 | 0
Energy-related derivatives | Alabama Power | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Derivative asset | 26 | 15
Liabilities: |  |
Derivative liability | 42 | 110
Energy-related derivatives | Alabama Power | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Derivative asset | 0 | 0
Liabilities: |  |
Derivative liability | 0 | 0
Energy-related derivatives | Georgia Power | Recurring |  |
Assets: |  |
Derivative asset | 19 | 13
Liabilities: |  |
Derivative liability | 42 | 124
Energy-related derivatives | Georgia Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Derivative asset | 0 | 0
Liabilities: |  |
Derivative liability | 0 | 0
Energy-related derivatives | Georgia Power | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Derivative asset | 19 | 13
Liabilities: |  |
Derivative liability | 42 | 124
Energy-related derivatives | Georgia Power | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Derivative asset | 0 | 0
Liabilities: |  |
Derivative liability | 0 | 0
Energy-related derivatives | Mississippi Power | Recurring |  |
Assets: |  |
Derivative asset | 19 | 15
Liabilities: |  |
Derivative liability | 34 | 61
Energy-related derivatives | Mississippi Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Derivative asset | 0 | 0
Liabilities: |  |
Derivative liability | 0 | 0
Energy-related derivatives | Mississippi Power | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Derivative asset | 19 | 15
Liabilities: |  |
Derivative liability | 34 | 61
Energy-related derivatives | Mississippi Power | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Derivative asset | 0 | 0
Liabilities: |  |
Derivative liability | 0 | 0
Energy-related derivatives | Southern Power | Recurring |  |
Assets: |  |
Derivative asset | 4 | 3
Liabilities: |  |
Derivative liability |  | 5
Energy-related derivatives | Southern Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Derivative asset | 0 | 0
Liabilities: |  |
Derivative liability |  | 0
Energy-related derivatives | Southern Power | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Derivative asset | 4 | 3
Liabilities: |  |
Derivative liability |  | 5
Energy-related derivatives | Southern Power | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Derivative asset | 0 | 0
Liabilities: |  |
Derivative liability |  | 0
Energy-related derivatives | Southern Company Gas | Recurring |  |
Assets: |  |
Derivative asset | 21 | 9
Liabilities: |  |
Derivative liability | 11 | 58
Energy-related derivatives | Southern Company Gas | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Derivative asset | 12 | 6
Liabilities: |  |
Derivative liability | 5 | 46
Energy-related derivatives | Southern Company Gas | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Derivative asset | 9 | 3
Liabilities: |  |
Derivative liability | 6 | 12
Energy-related derivatives | Southern Company Gas | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Derivative asset | 0 | 0
Liabilities: |  |
Derivative liability | 0 | 0
Interest rate derivatives | Recurring |  |
Liabilities: |  |
Derivative liability | 269 | 264
Interest rate derivatives | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Liabilities: |  |
Derivative liability | 0 | 0
Interest rate derivatives | Recurring | Significant Other Observable Inputs (Level 2) |  |
Liabilities: |  |
Derivative liability | 269 | 264
Interest rate derivatives | Recurring | Significant Unobservable Inputs (Level 3) |  |
Liabilities: |  |
Derivative liability | 0 | 0
Interest rate derivatives | Southern Company Gas | Recurring |  |
Liabilities: |  |
Derivative liability | 84 | 79
Interest rate derivatives | Southern Company Gas | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Liabilities: |  |
Derivative liability | 0 | 0
Interest rate derivatives | Southern Company Gas | Recurring | Significant Other Observable Inputs (Level 2) |  |
Liabilities: |  |
Derivative liability | 84 | 79
Interest rate derivatives | Southern Company Gas | Recurring | Significant Unobservable Inputs (Level 3) |  |
Liabilities: |  |
Derivative liability | 0 | 0
Foreign currency derivatives | Recurring |  |
Liabilities: |  |
Derivative liability | 218 | 122
Foreign currency derivatives | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Liabilities: |  |
Derivative liability | 0 | 0
Foreign currency derivatives | Recurring | Significant Other Observable Inputs (Level 2) |  |
Liabilities: |  |
Derivative liability | 218 | 122
Foreign currency derivatives | Recurring | Significant Unobservable Inputs (Level 3) |  |
Liabilities: |  |
Derivative liability | 0 | 0
Foreign currency derivatives | Southern Power | Recurring |  |
Liabilities: |  |
Derivative liability | 51 | 22
Contingent consideration |  | 19
Foreign currency derivatives | Southern Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Liabilities: |  |
Derivative liability | 0 | 0
Contingent consideration |  | 3
Foreign currency derivatives | Southern Power | Recurring | Significant Other Observable Inputs (Level 2) |  |
Liabilities: |  |
Derivative liability | 51 | 22
Contingent consideration |  | 0
Foreign currency derivatives | Southern Power | Recurring | Significant Unobservable Inputs (Level 3) |  |
Liabilities: |  |
Derivative liability | 0 | 0
Contingent consideration |  | 16
Domestic equity | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 1,099 | 980
Domestic equity | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 849 | 764
Domestic equity | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Nuclear decommissioning trusts | 250 | 216
Domestic equity | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Domestic equity | Alabama Power | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 700 | 651
Domestic equity | Alabama Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 459 | 443
Domestic equity | Alabama Power | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Nuclear decommissioning trusts | 241 | 208
Domestic equity | Alabama Power | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Domestic equity | Georgia Power | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 391 | 322
Domestic equity | Georgia Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 390 | 321
Domestic equity | Georgia Power | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Nuclear decommissioning trusts | 1 | 1
Domestic equity | Georgia Power | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Domestic equity | Southern Company Gas | Recurring |  |
Assets: |  |
Non-qualified deferred compensation trusts | 8 | 7
Domestic equity | Southern Company Gas | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Non-qualified deferred compensation trusts | 0 | 0
Domestic equity | Southern Company Gas | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Non-qualified deferred compensation trusts | 8 | 7
Domestic equity | Southern Company Gas | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Non-qualified deferred compensation trusts | 0 | 0
Foreign equity | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 323 | 316
Foreign equity | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 148 | 145
Foreign equity | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Nuclear decommissioning trusts | 175 | 171
Foreign equity | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Foreign equity | Alabama Power | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 148 | 145
Foreign equity | Alabama Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 148 | 145
Foreign equity | Alabama Power | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Foreign equity | Alabama Power | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Foreign equity | Georgia Power | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 174 | 170
Foreign equity | Georgia Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Foreign equity | Georgia Power | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Nuclear decommissioning trusts | 174 | 170
Foreign equity | Georgia Power | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Foreign equity | Southern Company Gas | Recurring |  |
Assets: |  |
Non-qualified deferred compensation trusts | 1 | 1
Foreign equity | Southern Company Gas | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Non-qualified deferred compensation trusts | 0 | 0
Foreign equity | Southern Company Gas | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Non-qualified deferred compensation trusts | 1 | 1
Foreign equity | Southern Company Gas | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Non-qualified deferred compensation trusts | 0 | 0
U.S. Treasury and government agency securities | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 371 | 369
Investments, available for sale: | 9 |
U.S. Treasury and government agency securities | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Investments, available for sale: | 2 |
U.S. Treasury and government agency securities | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Nuclear decommissioning trusts | 371 | 369
Investments, available for sale: | 7 |
U.S. Treasury and government agency securities | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Investments, available for sale: | 0 |
U.S. Treasury and government agency securities | Alabama Power | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 16 | 20
U.S. Treasury and government agency securities | Alabama Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
U.S. Treasury and government agency securities | Alabama Power | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Nuclear decommissioning trusts | 16 | 20
U.S. Treasury and government agency securities | Alabama Power | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
U.S. Treasury and government agency securities | Georgia Power | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 355 | 349
U.S. Treasury and government agency securities | Georgia Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
U.S. Treasury and government agency securities | Georgia Power | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Nuclear decommissioning trusts | 355 | 349
U.S. Treasury and government agency securities | Georgia Power | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
U.S. Treasury and government agency securities | Southern Company Gas | Recurring |  |
Assets: |  |
Investments, available for sale: | 9 |
U.S. Treasury and government agency securities | Southern Company Gas | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Investments, available for sale: | 2 |
U.S. Treasury and government agency securities | Southern Company Gas | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Investments, available for sale: | 7 |
U.S. Treasury and government agency securities | Southern Company Gas | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Investments, available for sale: | 0 |
Municipal bonds | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 47 | 48
Municipal bonds | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Municipal bonds | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Nuclear decommissioning trusts | 47 | 48
Municipal bonds | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Municipal bonds | Alabama Power | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 1 | 1
Municipal bonds | Alabama Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Municipal bonds | Alabama Power | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Nuclear decommissioning trusts | 1 | 1
Municipal bonds | Alabama Power | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Municipal bonds | Georgia Power | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 46 | 47
Municipal bonds | Georgia Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Municipal bonds | Georgia Power | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Nuclear decommissioning trusts | 46 | 47
Municipal bonds | Georgia Power | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Pooled funds – fixed income | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 7 | 6
Pooled funds – fixed income | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Pooled funds – fixed income | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Nuclear decommissioning trusts | 7 | 6
Pooled funds – fixed income | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Pooled funds – fixed income | Southern Company Gas | Recurring |  |
Assets: |  |
Non-qualified deferred compensation trusts | 7 | 6
Pooled funds – fixed income | Southern Company Gas | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Non-qualified deferred compensation trusts | 0 | 0
Pooled funds – fixed income | Southern Company Gas | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Non-qualified deferred compensation trusts | 7 | 6
Pooled funds – fixed income | Southern Company Gas | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Non-qualified deferred compensation trusts | 0 | 0
Corporate bonds | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 452 | 389
Investments, available for sale: | 3 |
Corporate bonds | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Investments, available for sale: | 1 |
Corporate bonds | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Nuclear decommissioning trusts | 452 | 389
Investments, available for sale: | 2 |
Corporate bonds | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Investments, available for sale: | 0 |
Corporate bonds | Alabama Power | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 287 | 231
Corporate bonds | Alabama Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Corporate bonds | Alabama Power | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Nuclear decommissioning trusts | 287 | 231
Corporate bonds | Alabama Power | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Corporate bonds | Georgia Power | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 165 | 158
Corporate bonds | Georgia Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Corporate bonds | Georgia Power | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Nuclear decommissioning trusts | 165 | 158
Corporate bonds | Georgia Power | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Corporate bonds | Southern Company Gas | Recurring |  |
Assets: |  |
Investments, available for sale: | 3 |
Corporate bonds | Southern Company Gas | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Investments, available for sale: | 1 |
Corporate bonds | Southern Company Gas | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Investments, available for sale: | 2 |
Corporate bonds | Southern Company Gas | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Investments, available for sale: | 0 |
Mortgage and asset backed securities | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 106 | 89
Investments, available for sale: | 10 |
Mortgage and asset backed securities | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Investments, available for sale: | 0 |
Mortgage and asset backed securities | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Nuclear decommissioning trusts | 106 | 89
Investments, available for sale: | 10 |
Mortgage and asset backed securities | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Investments, available for sale: | 0 |
Mortgage and asset backed securities | Alabama Power | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 31 | 25
Mortgage and asset backed securities | Alabama Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Mortgage and asset backed securities | Alabama Power | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Nuclear decommissioning trusts | 31 | 25
Mortgage and asset backed securities | Alabama Power | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Mortgage and asset backed securities | Georgia Power | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 75 | 64
Mortgage and asset backed securities | Georgia Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Mortgage and asset backed securities | Georgia Power | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Nuclear decommissioning trusts | 75 | 64
Mortgage and asset backed securities | Georgia Power | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Mortgage and asset backed securities | Southern Company Gas | Recurring |  |
Assets: |  |
Investments, available for sale: | 10 |
Mortgage and asset backed securities | Southern Company Gas | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Investments, available for sale: | 0 |
Mortgage and asset backed securities | Southern Company Gas | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Investments, available for sale: | 10 |
Mortgage and asset backed securities | Southern Company Gas | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Investments, available for sale: | 0 |
Private equity | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 181 | 169
Private equity | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Private equity | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Private equity | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Private equity | Recurring | Fair Value Measured at Net Asset Value Per Share (NAV) |  |
Assets: |  |
Nuclear decommissioning trusts | 181 | 169
Private equity | Alabama Power | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 181 | 169
Private equity | Alabama Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Private equity | Alabama Power | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Private equity | Alabama Power | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Private equity | Alabama Power | Recurring | Fair Value Measured at Net Asset Value Per Share (NAV) |  |
Assets: |  |
Nuclear decommissioning trusts | 181 | 169
Cash and cash equivalents | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 1 | 3
Cash and cash equivalents | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 1 | 3
Cash and cash equivalents | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Cash and cash equivalents | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Other | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 51 | 70
Other | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 39 | 58
Other | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Nuclear decommissioning trusts | 3 | 3
Other | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Other | Recurring | Fair Value Measured at Net Asset Value Per Share (NAV) |  |
Assets: |  |
Nuclear decommissioning trusts | 9 | 9
Other | Alabama Power | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 21 | 17
Other | Alabama Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 11 | 8
Other | Alabama Power | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Nuclear decommissioning trusts | 1 | 0
Other | Alabama Power | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Other | Alabama Power | Recurring | Fair Value Measured at Net Asset Value Per Share (NAV) |  |
Assets: |  |
Nuclear decommissioning trusts | 9 | 9
Other | Georgia Power | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 30 | 53
Other | Georgia Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 28 | 50
Other | Georgia Power | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Nuclear decommissioning trusts | 2 | 3
Other | Georgia Power | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Other | Southern Power | Recurring |  |
Liabilities: |  |
Derivative liability |  | 13
Other | Southern Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Liabilities: |  |
Derivative liability |  | 0
Other | Southern Power | Recurring | Significant Other Observable Inputs (Level 2) |  |
Liabilities: |  |
Derivative liability |  | 13
Other | Southern Power | Recurring | Significant Unobservable Inputs (Level 3) |  |
Liabilities: |  |
Derivative liability |  | 0
Cash and cash equivalents | Southern Company Gas | Recurring |  |
Assets: |  |
Non-qualified deferred compensation trusts | 1 | 3
Cash and cash equivalents | Southern Company Gas | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Non-qualified deferred compensation trusts | 1 | 3
Cash and cash equivalents | Southern Company Gas | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Non-qualified deferred compensation trusts | 0 | 0
Cash and cash equivalents | Southern Company Gas | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Non-qualified deferred compensation trusts | $ 0 | $ 0

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