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Segment Information - Electric and Gas Revenue by Customer Class (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2024 | Sep. 30, 2023
Revenue, Major Customer [Line Items] |  |  |  |
True-up adjustments to decoupling mechanisms and formula rates | $ (54) | $ 108 | $ (29) | $ 513
Total operating revenues | 6,154 | 5,980 | 17,557 | 16,360
Operating Segment |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Total operating revenues | 6,154 | 5,980 | 17,557 | 16,360
Operating Segment | Related Party |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Operating revenues from affiliates | 0 | 0 | 0 | 0
Commonwealth Edison Co |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
True-up adjustments to decoupling mechanisms and formula rates | (76) | 135 | (100) | 405
Total operating revenues | 2,229 | 2,268 | 6,403 | 5,836
Commonwealth Edison Co | Related Party |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Operating revenues from affiliates | 2 | 9 | 6 | 14
Commonwealth Edison Co | Regulated Operation |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Total operating revenues | 2,297 | 2,126 | 6,493 | 5,409
Commonwealth Edison Co | Other Regulated Revenue |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Total operating revenues | (68) | 142 | (90) | 427
PECO Energy Co |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
True-up adjustments to decoupling mechanisms and formula rates | 5 | 11 | 3 | 1
Total operating revenues | 1,030 | 1,037 | 2,975 | 2,977
PECO Energy Co | Related Party |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Operating revenues from affiliates | 4 | 2 | 7 | 6
PECO Energy Co | Regulated Operation |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Total operating revenues | 1,018 | 1,023 | 2,960 | 2,961
PECO Energy Co | Other Regulated Revenue |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Total operating revenues | 12 | 14 | 15 | 16
Baltimore Gas and Electric Company |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
True-up adjustments to decoupling mechanisms and formula rates | 9 | (22) | 28 | 47
Total operating revenues | 1,044 | 932 | 3,268 | 2,986
Baltimore Gas and Electric Company | Related Party |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Operating revenues from affiliates | 3 | 2 | 7 | 6
Baltimore Gas and Electric Company | Regulated Operation |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Total operating revenues | 1,030 | 949 | 3,231 | 2,922
Baltimore Gas and Electric Company | Other Regulated Revenue |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Total operating revenues | 14 | (17) | 37 | 64
Pepco Holdings LLC |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
True-up adjustments to decoupling mechanisms and formula rates | 8 | (15) | 40 | 59
Total operating revenues | 1,862 | 1,773 | 4,938 | 4,615
Pepco Holdings LLC | Related Party |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Operating revenues from affiliates | 3 | 2 | 7 | 7
Pepco Holdings LLC | Regulated Operation |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Total operating revenues | 1,850 | 1,785 | 4,887 | 4,545
Pepco Holdings LLC | Other Regulated Revenue |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Total operating revenues | 12 | (12) | 51 | 70
Potomac Electric Power Company |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
True-up adjustments to decoupling mechanisms and formula rates | 5 | (18) | 42 | 28
Total operating revenues | 861 | 822 | 2,320 | 2,174
Potomac Electric Power Company | Related Party |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Operating revenues from affiliates | 2 | 1 | 5 | 5
Potomac Electric Power Company | Regulated Operation |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Total operating revenues | 853 | 838 | 2,270 | 2,138
Potomac Electric Power Company | Other Regulated Revenue |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Total operating revenues | 8 | (16) | 50 | 36
Delmarva Power and Light Company |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
True-up adjustments to decoupling mechanisms and formula rates | (3) | (2) | 1 | 10
Total operating revenues | 462 | 450 | 1,343 | 1,273
Delmarva Power and Light Company | Related Party |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Operating revenues from affiliates | 2 | 2 | 5 | 5
Delmarva Power and Light Company | Regulated Operation |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Total operating revenues | 464 | 451 | 1,339 | 1,260
Delmarva Power and Light Company | Other Regulated Revenue |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Total operating revenues | (2) | (1) | 4 | 13
Atlantic City Electric Company |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
True-up adjustments to decoupling mechanisms and formula rates | 6 | 5 | (3) | 21
Total operating revenues | 540 | 502 | 1,280 | 1,172
Atlantic City Electric Company | Related Party |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Operating revenues from affiliates | 1 | 0 | 2 | 1
Atlantic City Electric Company | Regulated Operation |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Total operating revenues | 534 | 497 | 1,283 | 1,151
Atlantic City Electric Company | Other Regulated Revenue |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Total operating revenues | 6 | 5 | (3) | 21
Rate-regulated electric revenues |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 6,012 | 5,684 | 16,379 | 14,579
Rate-regulated electric revenues | Operating Segment |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 5,944 | 5,793 | 16,320 | 15,056
Rate-regulated electric revenues | Commonwealth Edison Co |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 2,303 | 2,124 | 6,497 | 5,417
Rate-regulated electric revenues | Commonwealth Edison Co | Regulated Operation |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 2,297 | 2,126 | 6,493 | 5,409
Rate-regulated electric revenues | Commonwealth Edison Co | Regulated Operation | Related Party |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Operating revenues from affiliates | 2 | 9 | 6 | 14
Rate-regulated electric revenues | Commonwealth Edison Co | Regulated Operation | Operating Segment |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 8 | 7 | 10 | 22
Rate-regulated electric revenues | Commonwealth Edison Co | Regulated Operation | Residential |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 1,117 | 1,047 | 3,017 | 2,744
Rate-regulated electric revenues | Commonwealth Edison Co | Regulated Operation | Small commercial & industrial |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 603 | 540 | 1,755 | 1,363
Rate-regulated electric revenues | Commonwealth Edison Co | Regulated Operation | Large commercial & industrial |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 286 | 263 | 875 | 553
Rate-regulated electric revenues | Commonwealth Edison Co | Regulated Operation | Public authorities & electric railroads |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 11 | 11 | 43 | 33
Rate-regulated electric revenues | Commonwealth Edison Co | Regulated Operation | Other |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 280 | 265 | 803 | 716
Rate-regulated electric revenues | PECO Energy Co |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 952 | 957 | 2,529 | 2,478
Rate-regulated electric revenues | PECO Energy Co | Regulated Operation |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 948 | 956 | 2,523 | 2,470
Rate-regulated electric revenues | PECO Energy Co | Regulated Operation | Related Party |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Operating revenues from affiliates | 3 | 2 | 5 | 5
Rate-regulated electric revenues | PECO Energy Co | Regulated Operation | Operating Segment |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 7 | 3 | 11 | 13
Rate-regulated electric revenues | PECO Energy Co | Regulated Operation | Residential |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 641 | 654 | 1,683 | 1,617
Rate-regulated electric revenues | PECO Energy Co | Regulated Operation | Small commercial & industrial |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 153 | 148 | 407 | 415
Rate-regulated electric revenues | PECO Energy Co | Regulated Operation | Large commercial & industrial |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 73 | 67 | 191 | 196
Rate-regulated electric revenues | PECO Energy Co | Regulated Operation | Public authorities & electric railroads |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 7 | 7 | 21 | 23
Rate-regulated electric revenues | PECO Energy Co | Regulated Operation | Other |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 74 | 80 | 221 | 219
Rate-regulated electric revenues | Baltimore Gas and Electric Company |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 928 | 856 | 2,585 | 2,306
Rate-regulated electric revenues | Baltimore Gas and Electric Company | Regulated Operation |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 926 | 853 | 2,582 | 2,298
Rate-regulated electric revenues | Baltimore Gas and Electric Company | Regulated Operation | Related Party |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Operating revenues from affiliates | 2 | 1 | 4 | 4
Rate-regulated electric revenues | Baltimore Gas and Electric Company | Regulated Operation | Operating Segment |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 4 | 4 | 7 | 12
Rate-regulated electric revenues | Baltimore Gas and Electric Company | Regulated Operation | Residential |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 558 | 512 | 1,556 | 1,308
Rate-regulated electric revenues | Baltimore Gas and Electric Company | Regulated Operation | Small commercial & industrial |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 96 | 86 | 274 | 253
Rate-regulated electric revenues | Baltimore Gas and Electric Company | Regulated Operation | Large commercial & industrial |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 154 | 144 | 425 | 412
Rate-regulated electric revenues | Baltimore Gas and Electric Company | Regulated Operation | Public authorities & electric railroads |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 8 | 7 | 24 | 22
Rate-regulated electric revenues | Baltimore Gas and Electric Company | Regulated Operation | Other |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 110 | 104 | 303 | 303
Rate-regulated electric revenues | Pepco Holdings LLC |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 1,828 | 1,762 | 4,769 | 4,399
Rate-regulated electric revenues | Pepco Holdings LLC | Regulated Operation |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 1,827 | 1,761 | 4,765 | 4,395
Rate-regulated electric revenues | Pepco Holdings LLC | Regulated Operation | Related Party |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Operating revenues from affiliates | 3 | 2 | 7 | 7
Rate-regulated electric revenues | Pepco Holdings LLC | Regulated Operation | Operating Segment |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 4 | 3 | 11 | 11
Rate-regulated electric revenues | Pepco Holdings LLC | Regulated Operation | Residential |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 1,016 | 959 | 2,537 | 2,181
Rate-regulated electric revenues | Pepco Holdings LLC | Regulated Operation | Small commercial & industrial |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 203 | 199 | 519 | 503
Rate-regulated electric revenues | Pepco Holdings LLC | Regulated Operation | Large commercial & industrial |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 365 | 386 | 1,034 | 1,099
Rate-regulated electric revenues | Pepco Holdings LLC | Regulated Operation | Public authorities & electric railroads |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 18 | 16 | 52 | 49
Rate-regulated electric revenues | Pepco Holdings LLC | Regulated Operation | Other |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 225 | 201 | 623 | 563
Rate-regulated electric revenues | Potomac Electric Power Company |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 854 | 839 | 2,273 | 2,141
Rate-regulated electric revenues | Potomac Electric Power Company | Regulated Operation |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 853 | 838 | 2,270 | 2,138
Rate-regulated electric revenues | Potomac Electric Power Company | Regulated Operation | Related Party |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Operating revenues from affiliates | 2 | 1 | 5 | 5
Rate-regulated electric revenues | Potomac Electric Power Company | Regulated Operation | Operating Segment |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 3 | 2 | 8 | 8
Rate-regulated electric revenues | Potomac Electric Power Company | Regulated Operation | Residential |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 426 | 405 | 1,085 | 954
Rate-regulated electric revenues | Potomac Electric Power Company | Regulated Operation | Small commercial & industrial |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 52 | 54 | 141 | 134
Rate-regulated electric revenues | Potomac Electric Power Company | Regulated Operation | Large commercial & industrial |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 281 | 303 | 794 | 838
Rate-regulated electric revenues | Potomac Electric Power Company | Regulated Operation | Public authorities & electric railroads |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 9 | 9 | 26 | 25
Rate-regulated electric revenues | Potomac Electric Power Company | Regulated Operation | Other |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 85 | 67 | 224 | 187
Rate-regulated electric revenues | Delmarva Power and Light Company |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 440 | 426 | 1,215 | 1,108
Rate-regulated electric revenues | Delmarva Power and Light Company | Regulated Operation |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 441 | 427 | 1,217 | 1,110
Rate-regulated electric revenues | Delmarva Power and Light Company | Regulated Operation | Related Party |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Operating revenues from affiliates | 2 | 2 | 5 | 5
Rate-regulated electric revenues | Delmarva Power and Light Company | Regulated Operation | Operating Segment |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 1 | 1 | 3 | 3
Rate-regulated electric revenues | Delmarva Power and Light Company | Regulated Operation | Residential |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 267 | 255 | 725 | 626
Rate-regulated electric revenues | Delmarva Power and Light Company | Regulated Operation | Small commercial & industrial |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 69 | 70 | 191 | 189
Rate-regulated electric revenues | Delmarva Power and Light Company | Regulated Operation | Large commercial & industrial |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 31 | 32 | 91 | 98
Rate-regulated electric revenues | Delmarva Power and Light Company | Regulated Operation | Public authorities & electric railroads |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 4 | 3 | 12 | 11
Rate-regulated electric revenues | Delmarva Power and Light Company | Regulated Operation | Other |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 70 | 67 | 198 | 186
Rate-regulated electric revenues | Atlantic City Electric Company |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 533 | 497 | 1,281 | 1,150
Rate-regulated electric revenues | Atlantic City Electric Company | Regulated Operation |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 534 | 497 | 1,283 | 1,151
Rate-regulated electric revenues | Atlantic City Electric Company | Regulated Operation | Related Party |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Operating revenues from affiliates | 1 | 0 | 2 | 1
Rate-regulated electric revenues | Atlantic City Electric Company | Regulated Operation | Operating Segment |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 0 | 0 | 0 | 0
Rate-regulated electric revenues | Atlantic City Electric Company | Regulated Operation | Residential |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 323 | 299 | 727 | 601
Rate-regulated electric revenues | Atlantic City Electric Company | Regulated Operation | Small commercial & industrial |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 82 | 75 | 187 | 180
Rate-regulated electric revenues | Atlantic City Electric Company | Regulated Operation | Large commercial & industrial |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 53 | 51 | 149 | 163
Rate-regulated electric revenues | Atlantic City Electric Company | Regulated Operation | Public authorities & electric railroads |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 5 | 4 | 14 | 13
Rate-regulated electric revenues | Atlantic City Electric Company | Regulated Operation | Other |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 71 | 68 | 206 | 194
Rate-regulated natural gas revenues |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 196 | 188 | 1,207 | 1,268
Rate-regulated natural gas revenues | Operating Segment |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 210 | 187 | 1,237 | 1,304
Rate-regulated natural gas revenues | Commonwealth Edison Co | Regulated Operation |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 0 | 0 | 0 | 0
Rate-regulated natural gas revenues | Commonwealth Edison Co | Regulated Operation | Operating Segment |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 0 | 0 | 0 | 0
Rate-regulated natural gas revenues | Commonwealth Edison Co | Regulated Operation | Residential |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 0 | 0 | 0 | 0
Rate-regulated natural gas revenues | Commonwealth Edison Co | Regulated Operation | Small commercial & industrial |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 0 | 0 | 0 | 0
Rate-regulated natural gas revenues | Commonwealth Edison Co | Regulated Operation | Large commercial & industrial |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 0 | 0 | 0 | 0
Rate-regulated natural gas revenues | Commonwealth Edison Co | Regulated Operation | Transportation |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 0 | 0 | 0 | 0
Rate-regulated natural gas revenues | Commonwealth Edison Co | Regulated Operation | Other |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 0 | 0 | 0 | 0
Rate-regulated natural gas revenues | PECO Energy Co |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 69 | 67 | 436 | 492
Rate-regulated natural gas revenues | PECO Energy Co | Regulated Operation |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 70 | 67 | 437 | 491
Rate-regulated natural gas revenues | PECO Energy Co | Regulated Operation | Related Party |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Operating revenues from affiliates | 1 | 0 | 2 | 1
Rate-regulated natural gas revenues | PECO Energy Co | Regulated Operation | Operating Segment |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 0 | 0 | 1 | 2
Rate-regulated natural gas revenues | PECO Energy Co | Regulated Operation | Residential |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 44 | 43 | 300 | 335
Rate-regulated natural gas revenues | PECO Energy Co | Regulated Operation | Small commercial & industrial |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 17 | 16 | 106 | 123
Rate-regulated natural gas revenues | PECO Energy Co | Regulated Operation | Large commercial & industrial |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 0 | 0 | 0 | 1
Rate-regulated natural gas revenues | PECO Energy Co | Regulated Operation | Transportation |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 7 | 7 | 20 | 20
Rate-regulated natural gas revenues | PECO Energy Co | Regulated Operation | Other |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 2 | 1 | 11 | 12
Rate-regulated natural gas revenues | Baltimore Gas and Electric Company |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 104 | 96 | 648 | 627
Rate-regulated natural gas revenues | Baltimore Gas and Electric Company | Regulated Operation |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 104 | 96 | 649 | 624
Rate-regulated natural gas revenues | Baltimore Gas and Electric Company | Regulated Operation | Related Party |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Operating revenues from affiliates | 1 | 1 | 3 | 2
Rate-regulated natural gas revenues | Baltimore Gas and Electric Company | Regulated Operation | Operating Segment |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 1 | 1 | 2 | 5
Rate-regulated natural gas revenues | Baltimore Gas and Electric Company | Regulated Operation | Residential |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 58 | 57 | 418 | 406
Rate-regulated natural gas revenues | Baltimore Gas and Electric Company | Regulated Operation | Small commercial & industrial |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 11 | 10 | 76 | 66
Rate-regulated natural gas revenues | Baltimore Gas and Electric Company | Regulated Operation | Large commercial & industrial |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 32 | 25 | 143 | 124
Rate-regulated natural gas revenues | Baltimore Gas and Electric Company | Regulated Operation | Transportation |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 0 | 0 | 0 | 0
Rate-regulated natural gas revenues | Baltimore Gas and Electric Company | Regulated Operation | Other |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 3 | 4 | 12 | 28
Rate-regulated natural gas revenues | Pepco Holdings LLC |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 23 | 24 | 122 | 150
Rate-regulated natural gas revenues | Pepco Holdings LLC | Regulated Operation |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 23 | 24 | 122 | 150
Rate-regulated natural gas revenues | Pepco Holdings LLC | Regulated Operation | Operating Segment |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 0 | 0 | 0 | 0
Rate-regulated natural gas revenues | Pepco Holdings LLC | Regulated Operation | Residential |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 11 | 12 | 72 | 88
Rate-regulated natural gas revenues | Pepco Holdings LLC | Regulated Operation | Small commercial & industrial |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 6 | 7 | 29 | 40
Rate-regulated natural gas revenues | Pepco Holdings LLC | Regulated Operation | Large commercial & industrial |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 1 | 1 | 4 | 3
Rate-regulated natural gas revenues | Pepco Holdings LLC | Regulated Operation | Transportation |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 4 | 3 | 12 | 11
Rate-regulated natural gas revenues | Pepco Holdings LLC | Regulated Operation | Other |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 1 | 1 | 5 | 8
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Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 0 | 0 | 0 | 0
Rate-regulated natural gas revenues | Potomac Electric Power Company | Regulated Operation | Operating Segment |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 0 | 0 | 0 | 0
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Revenue, Major Customer [Line Items] |  |  |  |
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Revenue, Major Customer [Line Items] |  |  |  |
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Revenue, Major Customer [Line Items] |  |  |  |
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Rate-regulated natural gas revenues | Potomac Electric Power Company | Regulated Operation | Other |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
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Revenue, Major Customer [Line Items] |  |  |  |
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Revenue, Major Customer [Line Items] |  |  |  |
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Revenue, Major Customer [Line Items] |  |  |  |
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Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 4 | 3 | 12 | 11
Rate-regulated natural gas revenues | Delmarva Power and Light Company | Regulated Operation | Other |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 1 | 1 | 5 | 8
Rate-regulated natural gas revenues | Atlantic City Electric Company | Regulated Operation |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 0 | 0 | 0 | 0
Rate-regulated natural gas revenues | Atlantic City Electric Company | Regulated Operation | Operating Segment |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 0 | 0 | 0 | 0
Rate-regulated natural gas revenues | Atlantic City Electric Company | Regulated Operation | Residential |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 0 | 0 | 0 | 0
Rate-regulated natural gas revenues | Atlantic City Electric Company | Regulated Operation | Small commercial & industrial |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 0 | 0 | 0 | 0
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Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 0 | 0 | 0 | 0
Rate-regulated natural gas revenues | Atlantic City Electric Company | Regulated Operation | Transportation |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 0 | 0 | 0 | 0
Rate-regulated natural gas revenues | Atlantic City Electric Company | Regulated Operation | Other |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Electric and natural gas operating revenues | 0 | 0 | 0 | 0
Alternative revenue programs | Commonwealth Edison Co | Regulated Operation | Operating Segment |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
True-up adjustments to decoupling mechanisms and formula rates | (76) | 135 | (100) | 405
Alternative revenue programs | PECO Energy Co | Regulated Operation | Operating Segment |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
True-up adjustments to decoupling mechanisms and formula rates | 5 | 11 | 3 | 1
Alternative revenue programs | Baltimore Gas and Electric Company | Regulated Operation | Operating Segment |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
True-up adjustments to decoupling mechanisms and formula rates | 9 | (22) | 28 | 47
Alternative revenue programs | Pepco Holdings LLC | Regulated Operation | Operating Segment |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
True-up adjustments to decoupling mechanisms and formula rates | 8 | (15) | 40 | 59
Alternative revenue programs | Potomac Electric Power Company | Regulated Operation | Operating Segment |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
True-up adjustments to decoupling mechanisms and formula rates | 5 | (18) | 42 | 28
Alternative revenue programs | Delmarva Power and Light Company | Regulated Operation | Operating Segment |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
True-up adjustments to decoupling mechanisms and formula rates | (3) | (2) | 1 | 10
Alternative revenue programs | Atlantic City Electric Company | Regulated Operation | Operating Segment |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
True-up adjustments to decoupling mechanisms and formula rates | $ 6 | $ 5 | $ (3) | $ 21

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