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FAIR VALUE MEASUREMENTS - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Millions | Dec. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Assets: |  |
Derivative asset | $ 213 | $ 281
Liabilities: |  |
Derivative liability | 125 | 64
Weather derivative premium |  | 6
Collateral already posted, aggregate fair value |  | 28
Recurring |  |
Assets: |  |
Cash equivalents | 1,174 | 584
Other investments | 44 | 33
Total | 4,023 | 3,759
Liabilities: |  |
Contingent consideration | 14 | 17
Other | 13 |
Total | 181 | 637
Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Cash equivalents | 1,160 | 575
Other investments | 9 | 9
Total | 2,174 | 1,974
Liabilities: |  |
Contingent consideration | 0 | 0
Other | 0 |
Total | 10 | 389
Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Cash equivalents | 14 | 9
Other investments | 35 | 24
Total | 1,699 | 1,677
Liabilities: |  |
Contingent consideration | 0 | 0
Other | 13 |
Total | 157 | 227
Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Cash equivalents | 0 | 0
Other investments | 0 | 0
Total | 0 | 32
Liabilities: |  |
Contingent consideration | 14 | 17
Other | 0 |
Total | 14 | 21
Recurring | Fair Value Measured at Net Asset Value Per Share (NAV) |  |
Assets: |  |
Total | 150 | 76
Alabama Power |  |
Assets: |  |
Derivative asset | 50 | 5
Liabilities: |  |
Derivative liability | 6 | 0
Alabama Power | Recurring |  |
Assets: |  |
Cash equivalents | 853 | 320
Other investments | 35 | 24
Total | 2,267 | 1,512
Alabama Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Cash equivalents | 839 | 311
Other investments | 0 | 0
Total | 1,482 | 959
Alabama Power | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Cash equivalents | 14 | 9
Other investments | 35 | 24
Total | 635 | 477
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 | 150 | 76
Georgia Power |  |
Assets: |  |
Derivative asset | 67 | 3
Liabilities: |  |
Derivative liability | 0 | 1
Georgia Power | Recurring |  |
Assets: |  |
Total | 1,292 | 1,160
Georgia Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Total | 336 | 340
Georgia Power | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Total | 956 | 820
Georgia Power | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Total | 0 | 0
Mississippi Power |  |
Assets: |  |
Derivative asset | 52 | 2
Liabilities: |  |
Derivative liability | 1 | 2
Mississippi Power | Recurring |  |
Assets: |  |
Cash equivalents | 40 | 21
Total | 96 | 30
Mississippi Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Cash equivalents | 40 | 21
Total | 40 | 21
Mississippi Power | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Cash equivalents | 0 | 0
Total | 56 | 9
Mississippi Power | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Cash equivalents | 0 | 0
Total | 0 | 0
Southern Power |  |
Assets: |  |
Derivative asset | 4 | 89
Liabilities: |  |
Derivative liability | 16 | 26
Southern Power | Recurring |  |
Assets: |  |
Total |  | 89
Liabilities: |  |
Contingent consideration | 14 | 17
Other | 13 |
Total | 43 | 43
Southern Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Total |  | 0
Liabilities: |  |
Contingent consideration | 0 | 0
Other | 0 |
Total | 0 | 0
Southern Power | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Total |  | 89
Liabilities: |  |
Contingent consideration | 0 | 0
Other | 13 |
Total | 29 | 26
Southern Power | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Total |  | 0
Liabilities: |  |
Contingent consideration | 14 | 17
Other | 0 |
Total | 14 | 17
Southern Company Gas |  |
Assets: |  |
Derivative asset | 27 | 162
Liabilities: |  |
Derivative liability | 16 | 35
Collateral already posted, aggregate fair value | 3 | 28
Southern Company Gas | Recurring |  |
Assets: |  |
Cash equivalents |  | 1
Total | 61 | 696
Liabilities: |  |
Total | 27 |
Southern Company Gas | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Cash equivalents |  | 1
Total | 26 | 402
Liabilities: |  |
Total | 10 |
Southern Company Gas | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Cash equivalents |  | 0
Total | 35 | 262
Liabilities: |  |
Total | 17 |
Southern Company Gas | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Cash equivalents |  | 0
Total | 0 | 32
Liabilities: |  |
Total | 0 |
Energy-related derivatives | Recurring |  |
Assets: |  |
Derivative asset | 219 | 704
Liabilities: |  |
Derivative liability | 46 | 597
Energy-related derivatives | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Derivative asset | 24 | 401
Liabilities: |  |
Derivative liability | 10 | 389
Energy-related derivatives | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Derivative asset | 195 | 271
Liabilities: |  |
Derivative liability | 36 | 204
Energy-related derivatives | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Derivative asset | 0 | 32
Liabilities: |  |
Derivative liability | 0 | 4
Energy-related derivatives | Alabama Power | Recurring |  |
Assets: |  |
Derivative asset | 55 | 12
Liabilities: |  |
Derivative liability | 11 | 7
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 | 55 | 12
Liabilities: |  |
Derivative liability | 11 | 7
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 | 75 | 15
Liabilities: |  |
Derivative liability | 8 | 13
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 | 75 | 15
Liabilities: |  |
Derivative liability | 8 | 13
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 | 56 | 9
Liabilities: |  |
Derivative liability | 5 | 9
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 | 56 | 9
Liabilities: |  |
Derivative liability | 5 | 9
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 | 2
Liabilities: |  |
Derivative liability |  | 3
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 | 2
Liabilities: |  |
Derivative liability |  | 3
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 | 29 | 666
Liabilities: |  |
Derivative liability | 22 | 565
Energy-related derivatives | Southern Company Gas | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Derivative asset | 24 | 401
Liabilities: |  |
Derivative liability | 10 | 389
Energy-related derivatives | Southern Company Gas | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Derivative asset | 5 | 233
Liabilities: |  |
Derivative liability | 12 | 172
Energy-related derivatives | Southern Company Gas | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Derivative asset | 0 | 32
Liabilities: |  |
Derivative liability | 0 | 4
Interest rate derivatives | Recurring |  |
Assets: |  |
Derivative asset | 19 | 20
Liabilities: |  |
Derivative liability | 29 |
Interest rate derivatives | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Derivative asset | 0 | 0
Liabilities: |  |
Derivative liability | 0 |
Interest rate derivatives | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Derivative asset | 19 | 20
Liabilities: |  |
Derivative liability | 29 |
Interest rate derivatives | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Derivative asset | 0 | 0
Liabilities: |  |
Derivative liability | 0 |
Interest rate derivatives | Southern Company Gas | Recurring |  |
Assets: |  |
Derivative asset | 6 |
Liabilities: |  |
Derivative liability | 5 |
Interest rate derivatives | Southern Company Gas | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Derivative asset | 0 |
Liabilities: |  |
Derivative liability | 0 |
Interest rate derivatives | Southern Company Gas | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Derivative asset | 6 |
Liabilities: |  |
Derivative liability | 5 |
Interest rate derivatives | Southern Company Gas | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Derivative asset | 0 |
Liabilities: |  |
Derivative liability | 0 |
Foreign currency derivatives | Recurring |  |
Assets: |  |
Derivative asset |  | 87
Liabilities: |  |
Derivative liability | 79 | 23
Foreign currency derivatives | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Derivative asset |  | 0
Liabilities: |  |
Derivative liability | 0 | 0
Foreign currency derivatives | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Derivative asset |  | 87
Liabilities: |  |
Derivative liability | 79 | 23
Foreign currency derivatives | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Derivative asset |  | 0
Liabilities: |  |
Derivative liability | 0 | 0
Foreign currency derivatives | Southern Power | Recurring |  |
Assets: |  |
Derivative asset |  | 87
Liabilities: |  |
Derivative liability | 16 | 23
Foreign currency derivatives | Southern Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Derivative asset |  | 0
Liabilities: |  |
Derivative liability | 0 | 0
Foreign currency derivatives | Southern Power | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Derivative asset |  | 87
Liabilities: |  |
Derivative liability | 16 | 23
Foreign currency derivatives | Southern Power | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Derivative asset |  | 0
Liabilities: |  |
Derivative liability | 0 | 0
Domestic equity | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 1,016 | 1,013
Domestic equity | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 791 | 862
Domestic equity | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Nuclear decommissioning trusts | 225 | 151
Domestic equity | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Domestic equity | Alabama Power | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 684 | 684
Domestic equity | Alabama Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 468 | 543
Domestic equity | Alabama Power | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Nuclear decommissioning trusts | 216 | 141
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 | 324 | 320
Domestic equity | Georgia Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 323 | 319
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 | 9
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 | 9
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 | 353 | 338
Foreign equity | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 165 | 85
Foreign equity | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Nuclear decommissioning trusts | 188 | 253
Foreign equity | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Foreign equity | Alabama Power | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 165 | 158
Foreign equity | Alabama Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 165 | 85
Foreign equity | Alabama Power | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 73
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 | 185 | 177
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 | 185 | 177
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 | 3 | 3
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 | 3 | 3
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 | 314 | 284
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 | 314 | 284
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 | 21 | 21
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 | 21 | 21
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 | 293 | 263
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 | 293 | 263
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 | 56 | 85
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 | 56 | 85
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 | 55 | 84
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 | 55 | 84
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 | 13 | 17
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 | 13 | 17
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 | 13 | 17
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 | 13 | 17
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 | 523 | 399
Corporate bonds | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 1 | 13
Corporate bonds | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Nuclear decommissioning trusts | 522 | 386
Corporate bonds | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Corporate bonds | Alabama Power | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 272 | 180
Corporate bonds | Alabama Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 1 | 13
Corporate bonds | Alabama Power | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Nuclear decommissioning trusts | 271 | 167
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 | 251 | 219
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 | 251 | 219
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 | 93 | 83
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 | 93 | 83
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 | 22 | 29
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 | 22 | 29
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 | 71 | 54
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 | 71 | 54
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 | 150 | 76
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 | 150 | 76
Private equity | Alabama Power | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 150 | 76
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 | 150 | 76
Cash and cash equivalents | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 2 | 1
Cash and cash equivalents | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 2 | 1
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 | 2 |
Cash equivalents | Southern Company Gas | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Non-qualified deferred compensation trusts | 2 |
Cash equivalents | Southern Company Gas | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Non-qualified deferred compensation trusts | 0 |
Cash equivalents | Southern Company Gas | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Non-qualified deferred compensation trusts | 0 |
Other | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 47 | 35
Other | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 22 | 28
Other | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Nuclear decommissioning trusts | 25 | 7
Other | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Nuclear decommissioning trusts | 0 | 0
Other | Alabama Power | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 9 | 7
Other | Alabama Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 9 | 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 | Georgia Power | Recurring |  |
Assets: |  |
Nuclear decommissioning trusts | 38 | 28
Other | Georgia Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Assets: |  |
Nuclear decommissioning trusts | 13 | 21
Other | Georgia Power | Recurring | Significant Other Observable Inputs (Level 2) |  |
Assets: |  |
Nuclear decommissioning trusts | 25 | 7
Other | Georgia Power | Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Nuclear decommissioning trusts | $ 0 | $ 0

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