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Revenue Recognition - Disaggregated Revenues (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Disaggregation of Revenue [Line Items] |  |  |
Revenue from contract with customer | $ 26,777 | $ 8,690 | $ 7,991
Mark-to-market for economic hedging activities | 2,716 | (119) | (20)
Revenues | 26,989 | 9,093 | 9,821
Less: Lease revenue | 8 | 18 | 20
Derivative revenue | 2,684 | (124) | 0
Retail Revenue | Home |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenue from contract with customer | 9,676 | 6,331 | 6,254
Retail Revenue | Business |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenue from contract with customer | 13,885 | 1,129 | 1,279
Total retail revenue |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenue from contract with customer | 23,561 | 7,460 | 7,533
Energy revenue |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenue from contract with customer | 1,215 | 539 | 1,169
Derivative revenue | 136 | 105 | 1,595
Capacity revenue |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenue from contract with customer | 775 | 680 | 700
Derivative revenue | 149 | 156 | 109
Derivative revenue |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Mark-to-market for economic hedging activities | (164) | 95 | 33
Derivative revenue | 234 | 385 | 1,810
Other revenue |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenue from contract with customer | 1,632 | 319 | 386
Contract amortization | (30) |  |
Total operating revenues |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 26,989 | 9,093 | 9,821
Other derivative revenue |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Derivative revenue | 113 | 29 | 73
Corporate/Eliminations |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenue from contract with customer | (6) | (7) | (5)
Revenues | 10 | (4) | (7)
Less: Lease revenue | 0 | 0 | 0
Corporate/Eliminations | Retail Revenue | Home |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenue from contract with customer | (1) | (2) | (3)
Corporate/Eliminations | Retail Revenue | Business |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenue from contract with customer | 0 | 0 | 0
Corporate/Eliminations | Total retail revenue |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenue from contract with customer | (1) | (2) | (3)
Corporate/Eliminations | Energy revenue |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenue from contract with customer | 7 | (1) | 0
Derivative revenue | 3 | (5) | (1)
Corporate/Eliminations | Capacity revenue |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenue from contract with customer | 0 | (1) | 0
Derivative revenue | 0 | 0 | 0
Corporate/Eliminations | Derivative revenue |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Mark-to-market for economic hedging activities | 13 | 8 | (1)
Derivative revenue | 16 | 3 | (2)
Corporate/Eliminations | Other revenue |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenue from contract with customer | (9) | (8) | (3)
Contract amortization | 0 |  |
Corporate/Eliminations | Total operating revenues |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 10 | (4) | (7)
Corporate/Eliminations | Other derivative revenue |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Derivative revenue | 0 | 0 | 0
Texas | Operating Segments |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenue from contract with customer | 10,163 | 6,279 | 5,507
Revenues | 10,293 | 6,309 | 7,069
Less: Lease revenue | 0 | 0 | 0
Texas | Operating Segments | Retail Revenue | Home |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenue from contract with customer | 5,665 | 5,027 | 5,027
Texas | Operating Segments | Retail Revenue | Business |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenue from contract with customer | 2,745 | 1,034 | 1,205
Texas | Operating Segments | Total retail revenue |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenue from contract with customer | 8,410 | 6,061 | 6,232
Texas | Operating Segments | Energy revenue |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenue from contract with customer | 329 | 24 | 529
Derivative revenue | 0 | 0 | 1,459
Texas | Operating Segments | Capacity revenue |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenue from contract with customer | 0 | 0 | 0
Derivative revenue | 0 | 0 | 0
Texas | Operating Segments | Derivative revenue |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Mark-to-market for economic hedging activities | (3) | 2 | 47
Derivative revenue | 130 | 30 | 1,562
Texas | Operating Segments | Other revenue |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenue from contract with customer | 1,557 | 222 | 261
Contract amortization | 0 |  |
Texas | Operating Segments | Total operating revenues |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 10,293 | 6,309 | 7,069
Texas | Operating Segments | Other ancillary revenue |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenue from contract with customer | 1,300 |  |
Texas | Operating Segments | Other derivative revenue |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Derivative revenue | 133 | 28 | 56
Texas | Corporate/Eliminations |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | (5) | (6) | (1)
East | Operating Segments |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenue from contract with customer | 12,874 | 1,943 | 2,078
Revenues | 13,033 | 2,258 | 2,262
Less: Lease revenue | 1 | 1 | 1
East | Operating Segments | Retail Revenue | Home |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenue from contract with customer | 1,959 | 1,210 | 1,173
East | Operating Segments | Retail Revenue | Business |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenue from contract with customer | 9,903 | 95 | 74
East | Operating Segments | Total retail revenue |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenue from contract with customer | 11,862 | 1,305 | 1,247
East | Operating Segments | Energy revenue |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenue from contract with customer | 508 | 183 | 322
Derivative revenue | 131 | 67 | 98
East | Operating Segments | Capacity revenue |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenue from contract with customer | 718 | 620 | 664
Derivative revenue | 149 | 156 | 109
East | Operating Segments | Derivative revenue |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Mark-to-market for economic hedging activities | (88) | 88 | (29)
Derivative revenue | 184 | 314 | 183
East | Operating Segments | Other revenue |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenue from contract with customer | 59 | 62 | 58
Contract amortization | (26) |  |
East | Operating Segments | Total operating revenues |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 13,033 | 2,258 | 2,262
East | Operating Segments | Other derivative revenue |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Derivative revenue | (8) | 3 | 5
East | Corporate/Eliminations |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 18 | 6 | (8)
West/Services/Other | Operating Segments |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenue from contract with customer | 3,746 | 475 | 411
Less: Lease revenue | 7 | 17 | 19
West/Services/Other | Operating Segments | Retail Revenue | Home |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenue from contract with customer | 2,053 | 96 | 57
West/Services/Other | Operating Segments | Retail Revenue | Business |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenue from contract with customer | 1,237 | 0 | 0
West/Services/Other | Operating Segments | Total retail revenue |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenue from contract with customer | 3,290 | 96 | 57
West/Services/Other | Operating Segments | Energy revenue |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenue from contract with customer | 371 | 333 | 318
Derivative revenue | 2 | 43 | 39
West/Services/Other | Operating Segments | Capacity revenue |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenue from contract with customer | 57 | 61 | 36
Derivative revenue | 0 | 0 | 0
West/Services/Other | Operating Segments | Derivative revenue |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Mark-to-market for economic hedging activities | (86) | (3) | 16
Derivative revenue | (96) | 38 | 67
West/Services/Other | Operating Segments | Other revenue |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenue from contract with customer | 25 | 43 | 70
Contract amortization | (4) |  |
West/Services/Other | Operating Segments | Total operating revenues |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 3,653 | 530 | 497
West/Services/Other | Operating Segments | Other derivative revenue |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Derivative revenue | $ (12) | $ (2) | $ 12

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