v3.23.3
Revenue from Contracts with Customers and Lease Income - Schedule of Disaggregation of Revenue (Details) - USD ($)
$ in Millions
 3 Months Ended 9 Months Ended
Sep. 30, 2023
Sep. 30, 2022
Sep. 30, 2023
Sep. 30, 2022
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers $ 7,107 $ 7,116 $ 18,886 $ 19,599
Total operating revenues 6,980 8,378 19,208 22,232
Retail electric revenues        
Disaggregation of Revenue [Line Items]        
Total operating revenues 5,139 5,961 12,597 14,363
Retail electric revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 5,534 4,951 13,035 12,477
Residential        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 2,543 2,104 5,717 5,282
Commercial        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 1,845 1,637 4,464 4,202
Industrial        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 1,116 1,183 2,770 2,914
Other        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 30 27 84 79
Natural Gas        
Disaggregation of Revenue [Line Items]        
Total operating revenues 689 857 3,417 3,998
Natural gas distribution revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 612 744 2,952 3,490
Residential        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 217 331 1,443 1,821
Commercial        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 56 93 370 493
Transportation        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 275 259 878 872
Industrial        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 4 12 33 60
Other        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 60 49 228 244
Wholesale electric revenues        
Disaggregation of Revenue [Line Items]        
Total operating revenues 727 1,197 1,930 2,798
Wholesale electric revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 569 1,045 1,542 2,364
PPA energy revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 317 812 853 1,739
PPA capacity revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 151 175 490 443
Non-PPA revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 101 58 199 182
Other natural gas revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 62 99 386 458
Gas marketing services        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 54 84 358 417
Other natural gas revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 8 15 28 41
Other revenue sources        
Disaggregation of Revenue [Line Items]        
Other revenues (127) 1,262 322 2,633
Other revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 330 277 971 810
ALABAMA POWER CO        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 2,230 2,128 5,638 5,315
Total operating revenues 2,083 2,444 5,420 6,023
ALABAMA POWER CO | Retail electric revenues        
Disaggregation of Revenue [Line Items]        
Total operating revenues 1,860 2,008 4,708 5,015
ALABAMA POWER CO | Retail electric revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 2,069 1,753 5,104 4,487
ALABAMA POWER CO | Residential        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 969 799 2,277 2,049
ALABAMA POWER CO | Commercial        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 599 499 1,493 1,285
ALABAMA POWER CO | Industrial        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 498 452 1,324 1,143
ALABAMA POWER CO | Other        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 3 3 10 10
ALABAMA POWER CO | Natural gas distribution revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
ALABAMA POWER CO | Residential        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
ALABAMA POWER CO | Commercial        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
ALABAMA POWER CO | Transportation        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
ALABAMA POWER CO | Industrial        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
ALABAMA POWER CO | Other        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
ALABAMA POWER CO | Wholesale electric revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 107 310 375 655
ALABAMA POWER CO | PPA energy revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 66 187 196 354
ALABAMA POWER CO | PPA capacity revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 26 56 130 135
ALABAMA POWER CO | Non-PPA revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 15 67 49 166
ALABAMA POWER CO | Other natural gas revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
ALABAMA POWER CO | Gas marketing services        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
ALABAMA POWER CO | Other natural gas revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
ALABAMA POWER CO | Other revenue sources        
Disaggregation of Revenue [Line Items]        
Other revenues (147) 316 (218) 708
ALABAMA POWER CO | Other revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 54 65 159 173
GEORGIA POWER CO        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 3,388 3,093 7,754 7,767
Total operating revenues 3,237 3,889 7,805 9,218
GEORGIA POWER CO | Retail electric revenues        
Disaggregation of Revenue [Line Items]        
Total operating revenues 2,996 3,703 7,142 8,629
GEORGIA POWER CO | Retail electric revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 3,177 2,927 7,198 7,274
GEORGIA POWER CO | Residential        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 1,473 1,212 3,202 2,995
GEORGIA POWER CO | Commercial        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 1,151 1,051 2,733 2,688
GEORGIA POWER CO | Industrial        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 528 642 1,195 1,529
GEORGIA POWER CO | Other        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 25 22 68 62
GEORGIA POWER CO | Natural gas distribution revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
GEORGIA POWER CO | Residential        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
GEORGIA POWER CO | Commercial        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
GEORGIA POWER CO | Transportation        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
GEORGIA POWER CO | Industrial        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
GEORGIA POWER CO | Other        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
GEORGIA POWER CO | Wholesale electric revenues        
Disaggregation of Revenue [Line Items]        
Total operating revenues 69 56 147 186
GEORGIA POWER CO | Wholesale electric revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 65 56 134 166
GEORGIA POWER CO | PPA energy revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 31 40 66 112
GEORGIA POWER CO | PPA capacity revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 13 12 38 35
GEORGIA POWER CO | Non-PPA revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 21 4 30 19
GEORGIA POWER CO | Other natural gas revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
GEORGIA POWER CO | Gas marketing services        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
GEORGIA POWER CO | Other natural gas revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
GEORGIA POWER CO | Other revenue sources        
Disaggregation of Revenue [Line Items]        
Other revenues (151) 796 51 1,451
GEORGIA POWER CO | Other revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 146 110 422 327
MISSISSIPPI POWER CO        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 440 531 1,123 1,276
Total operating revenues 436 510 1,137 1,279
MISSISSIPPI POWER CO | Retail electric revenues        
Disaggregation of Revenue [Line Items]        
Total operating revenues 284 250 747 718
MISSISSIPPI POWER CO | Retail electric revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 288 271 733 716
MISSISSIPPI POWER CO | Residential        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 101 93 238 238
MISSISSIPPI POWER CO | Commercial        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 95 87 238 229
MISSISSIPPI POWER CO | Industrial        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 90 89 251 242
MISSISSIPPI POWER CO | Other        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 2 2 6 7
MISSISSIPPI POWER CO | Natural gas distribution revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
MISSISSIPPI POWER CO | Residential        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
MISSISSIPPI POWER CO | Commercial        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
MISSISSIPPI POWER CO | Transportation        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
MISSISSIPPI POWER CO | Industrial        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
MISSISSIPPI POWER CO | Other        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
MISSISSIPPI POWER CO | Wholesale electric revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 142 247 359 526
MISSISSIPPI POWER CO | PPA energy revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 2 4 8 11
MISSISSIPPI POWER CO | PPA capacity revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 3 1 36 4
MISSISSIPPI POWER CO | Non-PPA revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 137 242 315 511
MISSISSIPPI POWER CO | Other natural gas revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
MISSISSIPPI POWER CO | Gas marketing services        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
MISSISSIPPI POWER CO | Other natural gas revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
MISSISSIPPI POWER CO | Other revenue sources        
Disaggregation of Revenue [Line Items]        
Other revenues (4) (21) 14 3
MISSISSIPPI POWER CO | Other revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 10 13 31 34
SOUTHERN POWER CO        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 480 1,010 1,248 2,157
Total operating revenues 653 1,180 1,686 2,618
SOUTHERN POWER CO | Retail electric revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
SOUTHERN POWER CO | Residential        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
SOUTHERN POWER CO | Commercial        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
SOUTHERN POWER CO | Industrial        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
SOUTHERN POWER CO | Other        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
SOUTHERN POWER CO | Natural gas distribution revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
SOUTHERN POWER CO | Residential        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
SOUTHERN POWER CO | Commercial        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
SOUTHERN POWER CO | Transportation        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
SOUTHERN POWER CO | Industrial        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
SOUTHERN POWER CO | Other        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
SOUTHERN POWER CO | Wholesale electric revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 462 1,001 1,202 2,130
SOUTHERN POWER CO | PPA energy revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 226 591 601 1,285
SOUTHERN POWER CO | PPA capacity revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 110 107 289 273
SOUTHERN POWER CO | Non-PPA revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 126 303 312 572
SOUTHERN POWER CO | Other natural gas revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
SOUTHERN POWER CO | Gas marketing services        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
SOUTHERN POWER CO | Other natural gas revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
SOUTHERN POWER CO | Other revenue sources        
Disaggregation of Revenue [Line Items]        
Other revenues 173 170 438 461
SOUTHERN POWER CO | Other revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 18 9 46 27
SOUTHERN Co GAS        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 674 843 3,338 3,948
Total operating revenues 689 857 3,417 3,998
SOUTHERN Co GAS | Retail electric revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
SOUTHERN Co GAS | Residential        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
SOUTHERN Co GAS | Commercial        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
SOUTHERN Co GAS | Industrial        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
SOUTHERN Co GAS | Other        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
SOUTHERN Co GAS | Natural gas distribution revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 612 744 2,952 3,490
SOUTHERN Co GAS | Residential        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 217 331 1,443 1,821
SOUTHERN Co GAS | Commercial        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 56 93 370 493
SOUTHERN Co GAS | Transportation        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 275 259 878 872
SOUTHERN Co GAS | Industrial        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 4 12 33 60
SOUTHERN Co GAS | Other        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 60 49 228 244
SOUTHERN Co GAS | Wholesale electric revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
SOUTHERN Co GAS | PPA energy revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
SOUTHERN Co GAS | PPA capacity revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
SOUTHERN Co GAS | Non-PPA revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
SOUTHERN Co GAS | Other natural gas revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 62 99 386 458
SOUTHERN Co GAS | Gas marketing services        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 54 84 358 417
SOUTHERN Co GAS | Other natural gas revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 8 15 28 41
SOUTHERN Co GAS | Other revenue sources        
Disaggregation of Revenue [Line Items]        
Other revenues 15 14 79 50
SOUTHERN Co GAS | Other revenues        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers $ 0 $ 0 $ 0 $ 0