Fair Value Measurements - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($)
$ in Millions |
Dec. 31, 2018 |
Dec. 31, 2017 |
| Liabilities: |
|
|
| Weather derivative premium |
$ 8
|
$ 11
|
| Collateral already posted, aggregate fair value |
277
|
193
|
| Recurring |
|
|
| Assets: |
|
|
| Foreign currency derivatives |
75
|
|
| Non-qualified deferred compensation trusts: |
|
|
| Cash equivalents |
766
|
1,455
|
| Other investments |
12
|
10
|
| Total |
3,387
|
3,995
|
| Liabilities: |
|
|
| Contingent consideration |
21
|
22
|
| Total |
1,057
|
816
|
| Recurring | Domestic equity |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
708
|
772
|
| Recurring | Foreign equity |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
226
|
286
|
| Recurring | U.S. Treasury and government agency securities |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
261
|
251
|
| Recurring | Municipal bonds |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
83
|
68
|
| Recurring | Pooled funds – fixed income |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
14
|
|
| Recurring | Corporate bonds |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
314
|
336
|
| Recurring | Mortgage- and asset-backed securities |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
68
|
57
|
| Recurring | Private equity |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
45
|
29
|
| Recurring | Cash and cash equivalents |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
16
|
|
| Recurring | Other |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
38
|
31
|
| Recurring | Energy-related derivatives |
|
|
| Assets: |
|
|
| Energy-related derivatives |
761
|
570
|
| Liabilities: |
|
|
| Energy-related derivatives |
964
|
733
|
| Recurring | Interest rate derivatives |
|
|
| Assets: |
|
|
| Interest rate derivatives |
|
1
|
| Liabilities: |
|
|
| Interest rate derivatives |
49
|
38
|
| Recurring | Foreign currency derivatives |
|
|
| Assets: |
|
|
| Foreign currency derivatives |
129
|
|
| Liabilities: |
|
|
| Foreign currency derivatives |
23
|
23
|
| Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |
|
|
| Assets: |
|
|
| Foreign currency derivatives |
0
|
|
| Non-qualified deferred compensation trusts: |
|
|
| Cash equivalents |
765
|
1,455
|
| Other investments |
0
|
9
|
| Total |
1,962
|
2,587
|
| Liabilities: |
|
|
| Contingent consideration |
0
|
0
|
| Total |
648
|
480
|
| Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Domestic equity |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
601
|
690
|
| Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Foreign equity |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
53
|
62
|
| Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | U.S. Treasury and government agency securities |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
0
|
0
|
| Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Municipal bonds |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
0
|
0
|
| Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Pooled funds – fixed income |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
0
|
|
| Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Corporate bonds |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
24
|
21
|
| Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Mortgage- and asset-backed securities |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
0
|
0
|
| Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Private equity |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
0
|
0
|
| Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Cash and cash equivalents |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
16
|
|
| Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Other |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
34
|
19
|
| Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Energy-related derivatives |
|
|
| Assets: |
|
|
| Energy-related derivatives |
469
|
331
|
| Liabilities: |
|
|
| Energy-related derivatives |
648
|
480
|
| Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Interest rate derivatives |
|
|
| Assets: |
|
|
| Interest rate derivatives |
|
0
|
| Liabilities: |
|
|
| Interest rate derivatives |
0
|
0
|
| Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Foreign currency derivatives |
|
|
| Assets: |
|
|
| Foreign currency derivatives |
0
|
|
| Liabilities: |
|
|
| Foreign currency derivatives |
0
|
0
|
| Recurring | Significant Other Observable Inputs (Level 2) |
|
|
| Assets: |
|
|
| Foreign currency derivatives |
75
|
|
| Non-qualified deferred compensation trusts: |
|
|
| Cash equivalents |
1
|
0
|
| Other investments |
12
|
0
|
| Total |
1,380
|
1,378
|
| Liabilities: |
|
|
| Contingent consideration |
0
|
0
|
| Total |
388
|
314
|
| Recurring | Significant Other Observable Inputs (Level 2) | Domestic equity |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
107
|
82
|
| Recurring | Significant Other Observable Inputs (Level 2) | Foreign equity |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
173
|
224
|
| Recurring | Significant Other Observable Inputs (Level 2) | U.S. Treasury and government agency securities |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
261
|
251
|
| Recurring | Significant Other Observable Inputs (Level 2) | Municipal bonds |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
83
|
68
|
| Recurring | Significant Other Observable Inputs (Level 2) | Pooled funds – fixed income |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
14
|
|
| Recurring | Significant Other Observable Inputs (Level 2) | Corporate bonds |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
290
|
315
|
| Recurring | Significant Other Observable Inputs (Level 2) | Mortgage- and asset-backed securities |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
68
|
57
|
| Recurring | Significant Other Observable Inputs (Level 2) | Private equity |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
0
|
0
|
| Recurring | Significant Other Observable Inputs (Level 2) | Cash and cash equivalents |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
0
|
|
| Recurring | Significant Other Observable Inputs (Level 2) | Other |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
4
|
12
|
| Recurring | Significant Other Observable Inputs (Level 2) | Energy-related derivatives |
|
|
| Assets: |
|
|
| Energy-related derivatives |
292
|
239
|
| Liabilities: |
|
|
| Energy-related derivatives |
316
|
253
|
| Recurring | Significant Other Observable Inputs (Level 2) | Interest rate derivatives |
|
|
| Assets: |
|
|
| Interest rate derivatives |
|
1
|
| Liabilities: |
|
|
| Interest rate derivatives |
49
|
38
|
| Recurring | Significant Other Observable Inputs (Level 2) | Foreign currency derivatives |
|
|
| Assets: |
|
|
| Foreign currency derivatives |
129
|
|
| Liabilities: |
|
|
| Foreign currency derivatives |
23
|
23
|
| Recurring | Significant Unobservable Inputs (Level 3) |
|
|
| Assets: |
|
|
| Foreign currency derivatives |
0
|
|
| Non-qualified deferred compensation trusts: |
|
|
| Cash equivalents |
0
|
0
|
| Other investments |
0
|
1
|
| Total |
0
|
1
|
| Liabilities: |
|
|
| Contingent consideration |
21
|
22
|
| Total |
21
|
22
|
| Recurring | Significant Unobservable Inputs (Level 3) | Domestic equity |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
0
|
0
|
| Recurring | Significant Unobservable Inputs (Level 3) | Foreign equity |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
0
|
0
|
| Recurring | Significant Unobservable Inputs (Level 3) | U.S. Treasury and government agency securities |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
0
|
0
|
| Recurring | Significant Unobservable Inputs (Level 3) | Municipal bonds |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
0
|
0
|
| Recurring | Significant Unobservable Inputs (Level 3) | Pooled funds – fixed income |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
0
|
|
| Recurring | Significant Unobservable Inputs (Level 3) | Corporate bonds |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
0
|
0
|
| Recurring | Significant Unobservable Inputs (Level 3) | Mortgage- and asset-backed securities |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
0
|
0
|
| Recurring | Significant Unobservable Inputs (Level 3) | Private equity |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
0
|
0
|
| Recurring | Significant Unobservable Inputs (Level 3) | Cash and cash equivalents |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
0
|
|
| Recurring | Significant Unobservable Inputs (Level 3) | Other |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
0
|
0
|
| Recurring | Significant Unobservable Inputs (Level 3) | Energy-related derivatives |
|
|
| Assets: |
|
|
| Energy-related derivatives |
0
|
0
|
| Liabilities: |
|
|
| Energy-related derivatives |
0
|
0
|
| Recurring | Significant Unobservable Inputs (Level 3) | Interest rate derivatives |
|
|
| Assets: |
|
|
| Interest rate derivatives |
|
0
|
| Liabilities: |
|
|
| Interest rate derivatives |
0
|
0
|
| Recurring | Significant Unobservable Inputs (Level 3) | Foreign currency derivatives |
|
|
| Assets: |
|
|
| Foreign currency derivatives |
0
|
|
| Liabilities: |
|
|
| Foreign currency derivatives |
0
|
0
|
| Recurring | Fair Value Measured at Net Asset Value Per Share |
|
|
| Non-qualified deferred compensation trusts: |
|
|
| Total |
45
|
29
|
| Recurring | Fair Value Measured at Net Asset Value Per Share | Private equity |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
45
|
29
|
| Alabama Power |
|
|
| Assets: |
|
|
| Energy-related derivatives |
6
|
4
|
| Liabilities: |
|
|
| Energy-related derivatives |
10
|
10
|
| Alabama Power | Recurring |
|
|
| Non-qualified deferred compensation trusts: |
|
|
| Cash equivalents |
117
|
349
|
| Other investments |
12
|
|
| Total |
981
|
1,255
|
| Alabama Power | Recurring | Domestic equity |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
491
|
523
|
| Alabama Power | Recurring | Foreign equity |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
103
|
121
|
| Alabama Power | Recurring | U.S. Treasury and government agency securities |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
18
|
24
|
| Alabama Power | Recurring | Municipal bonds |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
1
|
|
| Alabama Power | Recurring | Corporate bonds |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
159
|
181
|
| Alabama Power | Recurring | Mortgage- and asset-backed securities |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
23
|
18
|
| Alabama Power | Recurring | Private equity |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
45
|
29
|
| Alabama Power | Recurring | Other |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
6
|
6
|
| Alabama Power | Recurring | Energy-related derivatives |
|
|
| Assets: |
|
|
| Energy-related derivatives |
6
|
4
|
| Liabilities: |
|
|
| Energy-related derivatives |
10
|
10
|
| Alabama Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |
|
|
| Non-qualified deferred compensation trusts: |
|
|
| Cash equivalents |
116
|
349
|
| Other investments |
0
|
|
| Total |
595
|
880
|
| Alabama Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Domestic equity |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
396
|
442
|
| Alabama Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Foreign equity |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
53
|
62
|
| Alabama Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | U.S. Treasury and government agency securities |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
0
|
0
|
| Alabama Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Municipal bonds |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
0
|
|
| Alabama Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Corporate bonds |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
24
|
21
|
| Alabama Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Mortgage- and asset-backed securities |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
0
|
0
|
| Alabama Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Private equity |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
0
|
0
|
| Alabama Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Other |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
6
|
6
|
| Alabama Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Energy-related derivatives |
|
|
| Assets: |
|
|
| Energy-related derivatives |
0
|
0
|
| Liabilities: |
|
|
| Energy-related derivatives |
0
|
0
|
| Alabama Power | Recurring | Significant Other Observable Inputs (Level 2) |
|
|
| Non-qualified deferred compensation trusts: |
|
|
| Cash equivalents |
1
|
0
|
| Other investments |
12
|
|
| Total |
341
|
346
|
| Alabama Power | Recurring | Significant Other Observable Inputs (Level 2) | Domestic equity |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
95
|
81
|
| Alabama Power | Recurring | Significant Other Observable Inputs (Level 2) | Foreign equity |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
50
|
59
|
| Alabama Power | Recurring | Significant Other Observable Inputs (Level 2) | U.S. Treasury and government agency securities |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
18
|
24
|
| Alabama Power | Recurring | Significant Other Observable Inputs (Level 2) | Municipal bonds |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
1
|
|
| Alabama Power | Recurring | Significant Other Observable Inputs (Level 2) | Corporate bonds |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
135
|
160
|
| Alabama Power | Recurring | Significant Other Observable Inputs (Level 2) | Mortgage- and asset-backed securities |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
23
|
18
|
| Alabama Power | Recurring | Significant Other Observable Inputs (Level 2) | Private equity |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
0
|
0
|
| Alabama Power | Recurring | Significant Other Observable Inputs (Level 2) | Other |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
0
|
0
|
| Alabama Power | Recurring | Significant Other Observable Inputs (Level 2) | Energy-related derivatives |
|
|
| Assets: |
|
|
| Energy-related derivatives |
6
|
4
|
| Liabilities: |
|
|
| Energy-related derivatives |
10
|
10
|
| Alabama Power | Recurring | Significant Unobservable Inputs (Level 3) |
|
|
| Non-qualified deferred compensation trusts: |
|
|
| Cash equivalents |
0
|
0
|
| Other investments |
0
|
|
| Total |
0
|
0
|
| Alabama Power | Recurring | Significant Unobservable Inputs (Level 3) | Domestic equity |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
0
|
0
|
| Alabama Power | Recurring | Significant Unobservable Inputs (Level 3) | Foreign equity |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
0
|
0
|
| Alabama Power | Recurring | Significant Unobservable Inputs (Level 3) | U.S. Treasury and government agency securities |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
0
|
0
|
| Alabama Power | Recurring | Significant Unobservable Inputs (Level 3) | Municipal bonds |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
0
|
|
| Alabama Power | Recurring | Significant Unobservable Inputs (Level 3) | Corporate bonds |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
0
|
0
|
| Alabama Power | Recurring | Significant Unobservable Inputs (Level 3) | Mortgage- and asset-backed securities |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
0
|
0
|
| Alabama Power | Recurring | Significant Unobservable Inputs (Level 3) | Private equity |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
0
|
0
|
| Alabama Power | Recurring | Significant Unobservable Inputs (Level 3) | Other |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
0
|
0
|
| Alabama Power | Recurring | Significant Unobservable Inputs (Level 3) | Energy-related derivatives |
|
|
| Assets: |
|
|
| Energy-related derivatives |
0
|
0
|
| Liabilities: |
|
|
| Energy-related derivatives |
0
|
0
|
| Alabama Power | Recurring | Fair Value Measured at Net Asset Value Per Share |
|
|
| Non-qualified deferred compensation trusts: |
|
|
| Total |
45
|
29
|
| Alabama Power | Recurring | Fair Value Measured at Net Asset Value Per Share | Private equity |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
45
|
29
|
| Georgia Power |
|
|
| Assets: |
|
|
| Energy-related derivatives |
6
|
6
|
| Liabilities: |
|
|
| Energy-related derivatives |
23
|
24
|
| Georgia Power | Recurring |
|
|
| Non-qualified deferred compensation trusts: |
|
|
| Cash equivalents |
|
690
|
| Total |
879
|
1,625
|
| Liabilities: |
|
|
| Total |
23
|
24
|
| Georgia Power | Recurring | Domestic equity |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
206
|
249
|
| Georgia Power | Recurring | Foreign equity |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
119
|
166
|
| Georgia Power | Recurring | U.S. Treasury and government agency securities |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
243
|
227
|
| Georgia Power | Recurring | Municipal bonds |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
82
|
68
|
| Georgia Power | Recurring | Corporate bonds |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
155
|
155
|
| Georgia Power | Recurring | Mortgage- and asset-backed securities |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
45
|
40
|
| Georgia Power | Recurring | Other |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
23
|
24
|
| Georgia Power | Recurring | Energy-related derivatives |
|
|
| Assets: |
|
|
| Energy-related derivatives |
6
|
6
|
| Liabilities: |
|
|
| Energy-related derivatives |
21
|
19
|
| Georgia Power | Recurring | Interest rate derivatives |
|
|
| Liabilities: |
|
|
| Interest rate derivatives |
2
|
5
|
| Georgia Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |
|
|
| Non-qualified deferred compensation trusts: |
|
|
| Cash equivalents |
|
690
|
| Total |
224
|
950
|
| Liabilities: |
|
|
| Total |
0
|
0
|
| Georgia Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Domestic equity |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
205
|
248
|
| Georgia Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Foreign equity |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
0
|
0
|
| Georgia Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | U.S. Treasury and government agency securities |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
0
|
0
|
| Georgia Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Municipal bonds |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
0
|
0
|
| Georgia Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Corporate bonds |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
0
|
0
|
| Georgia Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Mortgage- and asset-backed securities |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
0
|
0
|
| Georgia Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Other |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
19
|
12
|
| Georgia Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Energy-related derivatives |
|
|
| Assets: |
|
|
| Energy-related derivatives |
0
|
0
|
| Liabilities: |
|
|
| Energy-related derivatives |
0
|
0
|
| Georgia Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Interest rate derivatives |
|
|
| Liabilities: |
|
|
| Interest rate derivatives |
0
|
0
|
| Georgia Power | Recurring | Significant Other Observable Inputs (Level 2) |
|
|
| Non-qualified deferred compensation trusts: |
|
|
| Cash equivalents |
|
0
|
| Total |
655
|
675
|
| Liabilities: |
|
|
| Total |
23
|
24
|
| Georgia Power | Recurring | Significant Other Observable Inputs (Level 2) | Domestic equity |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
1
|
1
|
| Georgia Power | Recurring | Significant Other Observable Inputs (Level 2) | Foreign equity |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
119
|
166
|
| Georgia Power | Recurring | Significant Other Observable Inputs (Level 2) | U.S. Treasury and government agency securities |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
243
|
227
|
| Georgia Power | Recurring | Significant Other Observable Inputs (Level 2) | Municipal bonds |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
82
|
68
|
| Georgia Power | Recurring | Significant Other Observable Inputs (Level 2) | Corporate bonds |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
155
|
155
|
| Georgia Power | Recurring | Significant Other Observable Inputs (Level 2) | Mortgage- and asset-backed securities |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
45
|
40
|
| Georgia Power | Recurring | Significant Other Observable Inputs (Level 2) | Other |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
4
|
12
|
| Georgia Power | Recurring | Significant Other Observable Inputs (Level 2) | Energy-related derivatives |
|
|
| Assets: |
|
|
| Energy-related derivatives |
6
|
6
|
| Liabilities: |
|
|
| Energy-related derivatives |
21
|
19
|
| Georgia Power | Recurring | Significant Other Observable Inputs (Level 2) | Interest rate derivatives |
|
|
| Liabilities: |
|
|
| Interest rate derivatives |
2
|
5
|
| Georgia Power | Recurring | Significant Unobservable Inputs (Level 3) |
|
|
| Non-qualified deferred compensation trusts: |
|
|
| Cash equivalents |
|
0
|
| Total |
0
|
0
|
| Liabilities: |
|
|
| Total |
0
|
0
|
| Georgia Power | Recurring | Significant Unobservable Inputs (Level 3) | Domestic equity |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
0
|
0
|
| Georgia Power | Recurring | Significant Unobservable Inputs (Level 3) | Foreign equity |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
0
|
0
|
| Georgia Power | Recurring | Significant Unobservable Inputs (Level 3) | U.S. Treasury and government agency securities |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
0
|
0
|
| Georgia Power | Recurring | Significant Unobservable Inputs (Level 3) | Municipal bonds |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
0
|
0
|
| Georgia Power | Recurring | Significant Unobservable Inputs (Level 3) | Corporate bonds |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
0
|
0
|
| Georgia Power | Recurring | Significant Unobservable Inputs (Level 3) | Mortgage- and asset-backed securities |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
0
|
0
|
| Georgia Power | Recurring | Significant Unobservable Inputs (Level 3) | Other |
|
|
| Nuclear decommissioning trusts: |
|
|
| Nuclear decommissioning trusts |
0
|
0
|
| Georgia Power | Recurring | Significant Unobservable Inputs (Level 3) | Energy-related derivatives |
|
|
| Assets: |
|
|
| Energy-related derivatives |
0
|
0
|
| Liabilities: |
|
|
| Energy-related derivatives |
0
|
0
|
| Georgia Power | Recurring | Significant Unobservable Inputs (Level 3) | Interest rate derivatives |
|
|
| Liabilities: |
|
|
| Interest rate derivatives |
0
|
0
|
| Mississippi Power |
|
|
| Assets: |
|
|
| Energy-related derivatives |
3
|
3
|
| Liabilities: |
|
|
| Energy-related derivatives |
9
|
9
|
| Mississippi Power | Recurring |
|
|
| Non-qualified deferred compensation trusts: |
|
|
| Cash equivalents |
255
|
224
|
| Total |
258
|
227
|
| Mississippi Power | Recurring | Energy-related derivatives |
|
|
| Assets: |
|
|
| Energy-related derivatives |
3
|
2
|
| Liabilities: |
|
|
| Energy-related derivatives |
9
|
9
|
| Mississippi Power | Recurring | Interest rate derivatives |
|
|
| Assets: |
|
|
| Interest rate derivatives |
|
1
|
| Mississippi Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |
|
|
| Non-qualified deferred compensation trusts: |
|
|
| Cash equivalents |
255
|
224
|
| Total |
255
|
224
|
| Mississippi Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Energy-related derivatives |
|
|
| Assets: |
|
|
| Energy-related derivatives |
0
|
0
|
| Liabilities: |
|
|
| Energy-related derivatives |
0
|
0
|
| Mississippi Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Interest rate derivatives |
|
|
| Assets: |
|
|
| Interest rate derivatives |
|
0
|
| Mississippi Power | Recurring | Significant Other Observable Inputs (Level 2) |
|
|
| Non-qualified deferred compensation trusts: |
|
|
| Cash equivalents |
0
|
0
|
| Total |
3
|
3
|
| Mississippi Power | Recurring | Significant Other Observable Inputs (Level 2) | Energy-related derivatives |
|
|
| Assets: |
|
|
| Energy-related derivatives |
3
|
2
|
| Liabilities: |
|
|
| Energy-related derivatives |
9
|
9
|
| Mississippi Power | Recurring | Significant Other Observable Inputs (Level 2) | Interest rate derivatives |
|
|
| Assets: |
|
|
| Interest rate derivatives |
|
1
|
| Mississippi Power | Recurring | Significant Unobservable Inputs (Level 3) |
|
|
| Non-qualified deferred compensation trusts: |
|
|
| Cash equivalents |
0
|
0
|
| Total |
0
|
0
|
| Mississippi Power | Recurring | Significant Unobservable Inputs (Level 3) | Energy-related derivatives |
|
|
| Assets: |
|
|
| Energy-related derivatives |
0
|
0
|
| Liabilities: |
|
|
| Energy-related derivatives |
0
|
0
|
| Mississippi Power | Recurring | Significant Unobservable Inputs (Level 3) | Interest rate derivatives |
|
|
| Assets: |
|
|
| Interest rate derivatives |
|
0
|
| Southern Power |
|
|
| Assets: |
|
|
| Energy-related derivatives |
79
|
132
|
| Liabilities: |
|
|
| Energy-related derivatives |
31
|
36
|
| Southern Power | Recurring |
|
|
| Non-qualified deferred compensation trusts: |
|
|
| Cash equivalents |
46
|
21
|
| Total |
125
|
153
|
| Liabilities: |
|
|
| Contingent consideration |
21
|
22
|
| Total |
52
|
58
|
| Southern Power | Recurring | Energy-related derivatives |
|
|
| Assets: |
|
|
| Energy-related derivatives |
4
|
3
|
| Liabilities: |
|
|
| Energy-related derivatives |
8
|
13
|
| Southern Power | Recurring | Foreign currency derivatives |
|
|
| Assets: |
|
|
| Foreign currency derivatives |
75
|
129
|
| Liabilities: |
|
|
| Foreign currency derivatives |
23
|
23
|
| Southern Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |
|
|
| Non-qualified deferred compensation trusts: |
|
|
| Cash equivalents |
46
|
21
|
| Total |
46
|
21
|
| Liabilities: |
|
|
| Contingent consideration |
0
|
0
|
| Total |
0
|
0
|
| Southern Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Energy-related derivatives |
|
|
| Assets: |
|
|
| Energy-related derivatives |
0
|
0
|
| Liabilities: |
|
|
| Energy-related derivatives |
0
|
0
|
| Southern Power | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Foreign currency derivatives |
|
|
| Assets: |
|
|
| Foreign currency derivatives |
0
|
0
|
| Liabilities: |
|
|
| Foreign currency derivatives |
0
|
0
|
| Southern Power | Recurring | Significant Other Observable Inputs (Level 2) |
|
|
| Non-qualified deferred compensation trusts: |
|
|
| Cash equivalents |
0
|
0
|
| Total |
79
|
132
|
| Liabilities: |
|
|
| Contingent consideration |
0
|
0
|
| Total |
31
|
36
|
| Southern Power | Recurring | Significant Other Observable Inputs (Level 2) | Energy-related derivatives |
|
|
| Assets: |
|
|
| Energy-related derivatives |
4
|
3
|
| Liabilities: |
|
|
| Energy-related derivatives |
8
|
13
|
| Southern Power | Recurring | Significant Other Observable Inputs (Level 2) | Foreign currency derivatives |
|
|
| Assets: |
|
|
| Foreign currency derivatives |
75
|
129
|
| Liabilities: |
|
|
| Foreign currency derivatives |
23
|
23
|
| Southern Power | Recurring | Significant Unobservable Inputs (Level 3) |
|
|
| Non-qualified deferred compensation trusts: |
|
|
| Cash equivalents |
0
|
0
|
| Total |
0
|
0
|
| Liabilities: |
|
|
| Contingent consideration |
21
|
22
|
| Total |
21
|
22
|
| Southern Power | Recurring | Significant Unobservable Inputs (Level 3) | Energy-related derivatives |
|
|
| Assets: |
|
|
| Energy-related derivatives |
0
|
0
|
| Liabilities: |
|
|
| Energy-related derivatives |
0
|
0
|
| Southern Power | Recurring | Significant Unobservable Inputs (Level 3) | Foreign currency derivatives |
|
|
| Assets: |
|
|
| Foreign currency derivatives |
0
|
0
|
| Liabilities: |
|
|
| Foreign currency derivatives |
0
|
0
|
| Southern Company Gas |
|
|
| Assets: |
|
|
| Energy-related derivatives |
741
|
554
|
| Liabilities: |
|
|
| Energy-related derivatives |
909
|
660
|
| Weather derivative premium |
8
|
11
|
| Collateral already posted, aggregate fair value |
277
|
193
|
| Southern Company Gas | Energy-related derivatives |
|
|
| Liabilities: |
|
|
| Collateral already posted, aggregate fair value |
|
6
|
| Southern Company Gas | Recurring |
|
|
| Non-qualified deferred compensation trusts: |
|
|
| Cash equivalents |
40
|
|
| Total |
814
|
|
| Southern Company Gas | Recurring | Domestic equity |
|
|
| Non-qualified deferred compensation trusts: |
|
|
| Non-qualified deferred compensation trusts |
11
|
|
| Southern Company Gas | Recurring | Foreign equity |
|
|
| Non-qualified deferred compensation trusts: |
|
|
| Non-qualified deferred compensation trusts |
4
|
|
| Southern Company Gas | Recurring | Pooled funds – fixed income |
|
|
| Non-qualified deferred compensation trusts: |
|
|
| Non-qualified deferred compensation trusts |
14
|
|
| Southern Company Gas | Recurring | Cash and cash equivalents |
|
|
| Non-qualified deferred compensation trusts: |
|
|
| Non-qualified deferred compensation trusts |
4
|
|
| Southern Company Gas | Recurring | Energy-related derivatives |
|
|
| Assets: |
|
|
| Energy-related derivatives |
741
|
|
| Liabilities: |
|
|
| Energy-related derivatives |
909
|
|
| Southern Company Gas | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |
|
|
| Non-qualified deferred compensation trusts: |
|
|
| Cash equivalents |
40
|
|
| Total |
513
|
|
| Southern Company Gas | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Domestic equity |
|
|
| Non-qualified deferred compensation trusts: |
|
|
| Non-qualified deferred compensation trusts |
0
|
|
| Southern Company Gas | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Foreign equity |
|
|
| Non-qualified deferred compensation trusts: |
|
|
| Non-qualified deferred compensation trusts |
0
|
|
| Southern Company Gas | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Pooled funds – fixed income |
|
|
| Non-qualified deferred compensation trusts: |
|
|
| Non-qualified deferred compensation trusts |
0
|
|
| Southern Company Gas | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Cash and cash equivalents |
|
|
| Non-qualified deferred compensation trusts: |
|
|
| Non-qualified deferred compensation trusts |
4
|
|
| Southern Company Gas | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Energy-related derivatives |
|
|
| Assets: |
|
|
| Energy-related derivatives |
469
|
|
| Liabilities: |
|
|
| Energy-related derivatives |
648
|
|
| Southern Company Gas | Recurring | Significant Other Observable Inputs (Level 2) |
|
|
| Non-qualified deferred compensation trusts: |
|
|
| Cash equivalents |
0
|
|
| Total |
301
|
|
| Southern Company Gas | Recurring | Significant Other Observable Inputs (Level 2) | Domestic equity |
|
|
| Non-qualified deferred compensation trusts: |
|
|
| Non-qualified deferred compensation trusts |
11
|
|
| Southern Company Gas | Recurring | Significant Other Observable Inputs (Level 2) | Foreign equity |
|
|
| Non-qualified deferred compensation trusts: |
|
|
| Non-qualified deferred compensation trusts |
4
|
|
| Southern Company Gas | Recurring | Significant Other Observable Inputs (Level 2) | Pooled funds – fixed income |
|
|
| Non-qualified deferred compensation trusts: |
|
|
| Non-qualified deferred compensation trusts |
14
|
|
| Southern Company Gas | Recurring | Significant Other Observable Inputs (Level 2) | Cash and cash equivalents |
|
|
| Non-qualified deferred compensation trusts: |
|
|
| Non-qualified deferred compensation trusts |
0
|
|
| Southern Company Gas | Recurring | Significant Other Observable Inputs (Level 2) | Energy-related derivatives |
|
|
| Assets: |
|
|
| Energy-related derivatives |
272
|
|
| Liabilities: |
|
|
| Energy-related derivatives |
261
|
|
| Southern Company Gas | Recurring | Significant Unobservable Inputs (Level 3) |
|
|
| Non-qualified deferred compensation trusts: |
|
|
| Cash equivalents |
0
|
|
| Total |
0
|
|
| Southern Company Gas | Recurring | Significant Unobservable Inputs (Level 3) | Domestic equity |
|
|
| Non-qualified deferred compensation trusts: |
|
|
| Non-qualified deferred compensation trusts |
0
|
|
| Southern Company Gas | Recurring | Significant Unobservable Inputs (Level 3) | Foreign equity |
|
|
| Non-qualified deferred compensation trusts: |
|
|
| Non-qualified deferred compensation trusts |
0
|
|
| Southern Company Gas | Recurring | Significant Unobservable Inputs (Level 3) | Pooled funds – fixed income |
|
|
| Non-qualified deferred compensation trusts: |
|
|
| Non-qualified deferred compensation trusts |
0
|
|
| Southern Company Gas | Recurring | Significant Unobservable Inputs (Level 3) | Cash and cash equivalents |
|
|
| Non-qualified deferred compensation trusts: |
|
|
| Non-qualified deferred compensation trusts |
0
|
|
| Southern Company Gas | Recurring | Significant Unobservable Inputs (Level 3) | Energy-related derivatives |
|
|
| Assets: |
|
|
| Energy-related derivatives |
0
|
|
| Liabilities: |
|
|
| Energy-related derivatives |
$ 0
|
|
| Predecessor | Southern Company Gas | Recurring | Energy-related derivatives |
|
|
| Assets: |
|
|
| Energy-related derivatives |
|
554
|
| Liabilities: |
|
|
| Energy-related derivatives |
|
660
|
| Predecessor | Southern Company Gas | Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Energy-related derivatives |
|
|
| Assets: |
|
|
| Energy-related derivatives |
|
331
|
| Liabilities: |
|
|
| Energy-related derivatives |
|
479
|
| Predecessor | Southern Company Gas | Recurring | Significant Other Observable Inputs (Level 2) | Energy-related derivatives |
|
|
| Assets: |
|
|
| Energy-related derivatives |
|
223
|
| Liabilities: |
|
|
| Energy-related derivatives |
|
181
|
| Predecessor | Southern Company Gas | Recurring | Significant Unobservable Inputs (Level 3) | Energy-related derivatives |
|
|
| Assets: |
|
|
| Energy-related derivatives |
|
0
|
| Liabilities: |
|
|
| Energy-related derivatives |
|
$ 0
|