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FAIR VALUE MEASUREMENTS - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Millions | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Assets: |  |
Derivative asset | $ 32 | $ 141
Liabilities: |  |
Derivative liability | 659 | 617
Collateral already posted, aggregate fair value | 62 |
Recurring |  |
Assets: |  |
Cash equivalents | 268 | 1,447
Other investments | 44 | 35
Total | 2,806 | 3,856
Liabilities: |  |
Contingent consideration | 19 | 12
Other | 13 |
Total | 776 | 753
Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Cash equivalents | 253 | 1,427
Other investments | 9 | 9
Total | 1,238 | 2,271
Liabilities: |  |
Contingent consideration | 3 | 0
Other | 0 |
Total | 49 | 32
Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Cash equivalents | 15 | 20
Other investments | 27 | 26
Total | 1,382 | 1,424
Liabilities: |  |
Contingent consideration | 0 | 0
Other | 13 |
Total | 711 | 709
Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Cash equivalents | 0 | 0
Other investments | 8 | 0
Total | 8 | 0
Liabilities: |  |
Contingent consideration | 16 | 12
Other | 0 |
Total | 16 | 12
Recurring | Fair Value Measured at Net Asset Value Per Share (NAV) |  |
Assets: |  |
Total | 178 | 161
Alabama Power |  |
Assets: |  |
Derivative asset | 5 | 38
Liabilities: |  |
Derivative liability | 100 | 15
Collateral already posted, aggregate fair value | 0 |
Alabama Power | Recurring |  |
Assets: |  |
Cash equivalents | 134 | 458
Other investments | 27 | 26
Total | 1,435 | 1,671
Alabama Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Cash equivalents | 119 | 438
Other investments | 0 | 0
Total | 715 | 966
Alabama Power | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Cash equivalents | 15 | 20
Other investments | 27 | 26
Total | 542 | 544
Alabama Power | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Cash equivalents | 0 | 0
Other investments | 0 | 0
Total | 0 | 0
Alabama Power | Recurring | Fair Value Measured at Net Asset Value Per Share (NAV) |  |
Assets: |  |
Total | 178 | 161
Georgia Power |  |
Assets: |  |
Derivative asset | 2 | 21
Liabilities: |  |
Derivative liability | 113 | 41
Georgia Power | Recurring |  |
Assets: |  |
Cash equivalents |  | 355
Total | 1,176 | 1,415
Georgia Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Cash equivalents |  | 355
Total | 371 | 640
Georgia Power | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Cash equivalents |  | 0
Total | 805 | 775
Georgia Power | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Cash equivalents |  | 0
Total | 0 | 0
Mississippi Power |  |
Assets: |  |
Derivative asset | 1 | 42
Liabilities: |  |
Derivative liability | 47 | 15
Mississippi Power | Recurring |  |
Assets: |  |
Cash equivalents | 17 | 47
Total | 32 | 106
Mississippi Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Cash equivalents | 17 | 47
Total | 17 | 47
Mississippi Power | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Cash equivalents | 0 | 0
Total | 15 | 59
Mississippi Power | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Cash equivalents | 0 | 0
Total | 0 | 0
Southern Power |  |
Assets: |  |
Derivative asset | 3 | 8
Liabilities: |  |
Derivative liability | 27 | 59
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 |  |
Liabilities: |  |
Contingent consideration | 19 |
Other | 13 |
Total | 59 | 84
Southern Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Liabilities: |  |
Contingent consideration | 3 |
Other | 0 |
Total | 3 | 0
Southern Power | Recurring | Significant Other Observable Inputs (Level 2) |  |
Liabilities: |  |
Contingent consideration | 0 |
Other | 13 |
Total | 40 | 72
Southern Power | Recurring | Significant Unobservable Inputs (Level 3) |  |
Liabilities: |  |
Contingent consideration | 16 |
Other | 0 |
Total | 16 | 12
Southern Company Gas |  |
Assets: |  |
Derivative asset | 21 | 28
Liabilities: |  |
Derivative liability | 87 | 110
Collateral already posted, aggregate fair value | 62 | 41
Southern Company Gas | Recurring |  |
Assets: |  |
Cash equivalents |  | 50
Total | 26 | 98
Liabilities: |  |
Total | 137 | 151
Southern Company Gas | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Cash equivalents |  | 50
Total | 9 | 72
Liabilities: |  |
Total | 46 | 32
Southern Company Gas | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Cash equivalents |  | 0
Total | 17 | 26
Liabilities: |  |
Total | 91 | 119
Southern Company Gas | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Cash equivalents |  | 0
Total | 0 | 0
Liabilities: |  |
Total | 0 | 0
Energy-related derivatives | Recurring |  |
Assets: |  |
Derivative asset | 55 | 199
Liabilities: |  |
Derivative liability | 358 | 210
Energy-related derivatives | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Derivative asset | 6 | 18
Liabilities: |  |
Derivative liability | 46 | 32
Energy-related derivatives | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Derivative asset | 49 | 181
Liabilities: |  |
Derivative liability | 312 | 178
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 | 15 | 62
Liabilities: |  |
Derivative liability | 110 | 39
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 | 15 | 62
Liabilities: |  |
Derivative liability | 110 | 39
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 | 13 | 42
Liabilities: |  |
Derivative liability | 124 | 62
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 | 13 | 42
Liabilities: |  |
Derivative liability | 124 | 62
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 | 15 | 59
Liabilities: |  |
Derivative liability | 61 | 32
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 | 15 | 59
Liabilities: |  |
Derivative liability | 61 | 32
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 | 3 | 8
Liabilities: |  |
Derivative liability | 5 | 12
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 | 0
Energy-related derivatives | Southern Power | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Derivative asset | 3 | 8
Liabilities: |  |
Derivative liability | 5 | 12
Energy-related derivatives | Southern Power | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Derivative asset | 0 | 0
Liabilities: |  |
Derivative liability | 0 | 0
Energy-related derivatives | Southern Company Gas | Recurring |  |
Assets: |  |
Derivative asset | 9 | 28
Liabilities: |  |
Derivative liability | 58 | 65
Energy-related derivatives | Southern Company Gas | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Derivative asset | 6 | 18
Liabilities: |  |
Derivative liability | 46 | 32
Energy-related derivatives | Southern Company Gas | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Derivative asset | 3 | 10
Liabilities: |  |
Derivative liability | 12 | 33
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 |  |
Assets: |  |
Derivative asset |  | 12
Liabilities: |  |
Derivative liability | 264 | 302
Interest rate derivatives | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Derivative asset |  | 0
Liabilities: |  |
Derivative liability | 0 | 0
Interest rate derivatives | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Derivative asset |  | 12
Liabilities: |  |
Derivative liability | 264 | 302
Interest rate derivatives | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Derivative asset |  | 0
Liabilities: |  |
Derivative liability | 0 | 0
Interest rate derivatives | Southern Company Gas | Recurring |  |
Liabilities: |  |
Derivative liability | 79 | 86
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 | 79 | 86
Interest rate derivatives | Southern Company Gas | Recurring | Significant Unobservable Inputs (Level 3) |  |
Liabilities: |  |
Derivative liability | 0 | 0
Foreign currency derivatives | Recurring |  |
Liabilities: |  |
Derivative liability | 122 | 216
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 | 122 | 216
Foreign currency derivatives | Recurring | Significant Unobservable Inputs (Level 3) |  |
Liabilities: |  |
Derivative liability | 0 | 0
Foreign currency derivatives | Southern Power | Recurring |  |
Liabilities: |  |
Derivative liability | 22 | 47
Contingent consideration |  | 12
Foreign currency derivatives | Southern Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Liabilities: |  |
Derivative liability | 0 | 0
Contingent consideration |  | 0
Foreign currency derivatives | Southern Power | Recurring | Significant Other Observable Inputs (Level 2) |  |
Liabilities: |  |
Derivative liability | 22 | 47
Contingent consideration |  | 0
Foreign currency derivatives | Southern Power | Recurring | Significant Unobservable Inputs (Level 3) |  |
Liabilities: |  |
Derivative liability | 0 | 0
Contingent consideration |  | 12
Domestic equity | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 980 | 829
Domestic equity | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 764 | 651
Domestic equity | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Nuclear decommissioning trusts | 216 | 178
Domestic equity | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Domestic equity | Alabama Power | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 651 | 565
Domestic equity | Alabama Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 443 | 396
Domestic equity | Alabama Power | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Nuclear decommissioning trusts | 208 | 169
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 | 322 | 256
Domestic equity | Georgia Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 321 | 255
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 | 7 | 8
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 | 7 | 8
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 | 316 | 275
Foreign equity | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 145 | 125
Foreign equity | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Nuclear decommissioning trusts | 171 | 150
Foreign equity | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Foreign equity | Alabama Power | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 145 | 125
Foreign equity | Alabama Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 145 | 125
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 | 170 | 149
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 | 170 | 149
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 | 369 | 285
U.S. Treasury and government agency securities | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
U.S. Treasury and government agency securities | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Nuclear decommissioning trusts | 369 | 285
U.S. Treasury and government agency securities | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
U.S. Treasury and government agency securities | Alabama Power | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 20 | 19
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 | 20 | 19
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 | 349 | 266
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 | 349 | 266
U.S. Treasury and government agency securities | Georgia Power | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Municipal bonds | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 48 | 51
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 | 48 | 51
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 | 47 | 50
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 | 47 | 50
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 | 6 | 7
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 | 6 | 7
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 | 6 | 7
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 | 6 | 7
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 | 389 | 412
Corporate bonds | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Corporate bonds | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Nuclear decommissioning trusts | 389 | 412
Corporate bonds | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Corporate bonds | Alabama Power | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 231 | 225
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 | 231 | 225
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 | 158 | 187
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 | 158 | 187
Corporate bonds | Georgia Power | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Mortgage and asset backed securities | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 89 | 90
Mortgage and asset backed securities | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Mortgage and asset backed securities | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Nuclear decommissioning trusts | 89 | 90
Mortgage and asset backed securities | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Mortgage and asset backed securities | Alabama Power | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 25 | 22
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 | 25 | 22
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 | 64 | 68
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 | 64 | 68
Mortgage and asset backed securities | Georgia Power | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Private equity | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 169 | 161
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 | 169 | 161
Private equity | Alabama Power | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 169 | 161
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 | 169 | 161
Cash and cash equivalents | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 3 | 4
Cash and cash equivalents | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 3 | 4
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
Cash equivalents | Southern Company Gas | Recurring |  |
Assets: |  |
Non-qualified deferred compensation trusts | 3 | 4
Cash equivalents | Southern Company Gas | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Non-qualified deferred compensation trusts | 3 | 4
Cash equivalents | Southern Company Gas | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Non-qualified deferred compensation trusts | 0 | 0
Cash equivalents | Southern Company Gas | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Non-qualified deferred compensation trusts | 0 | 0
Other | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 70 | 49
Other | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 58 | 37
Other | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Nuclear decommissioning trusts | 3 | 12
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 |
Other | Alabama Power | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 17 | 7
Other | Alabama Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 8 | 7
Other | Alabama Power | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 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 |
Other | Georgia Power | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 53 | 42
Other | Georgia Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 50 | 30
Other | Georgia Power | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Nuclear decommissioning trusts | 3 | 12
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

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