v3.25.2
Reportable Segments - Schedule of Financial Data (Details) - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended
Jun. 30, 2025
Jun. 30, 2024
Jun. 30, 2025
Jun. 30, 2024
Dec. 31, 2024
Segment Reporting Information [Line Items]          
Revenues from external customers $ 1,944 $ 1,905 $ 4,864 $ 4,525  
Intersegment revenues 0   0    
Utility natural gas, fuel and purchased power 300 233 1,306 1,020  
Non-utility cost of revenues, including natural gas 2   3 1  
Operation and maintenance 715 678 1,462 1,387  
Depreciation and amortization 370 386 733 749  
Taxes other than income taxes 140 141 294 285  
Interest expense 195 217 433 421  
Income tax expense (benefit) 55 33 136 111  
Interest income 0 0 0 0  
Other expense (income), net (31) (11) 2 (27)  
Net income (loss) 198 228 495 578  
Interest income from securitization bonds (less than for 2025) 1 1 1 2  
Expenditures for Long-lived Assets     2,430 1,670  
Total Assets 44,099   44,099   $ 43,768
Natural Gas          
Segment Reporting Information [Line Items]          
Revenues from external customers 750 695 2,602 2,265  
Corporate and Other          
Segment Reporting Information [Line Items]          
Revenues from external customers 3 3 5 4  
Corporate and Other | Pension and Other Postretirement Plans Costs          
Segment Reporting Information [Line Items]          
Regulatory assets 372   372   384
Operating Segments          
Segment Reporting Information [Line Items]          
Revenues from external customers 1,944 1,905 4,864 4,525  
Intersegment revenues 1   2    
Utility natural gas, fuel and purchased power 301 233 1,308 1,020  
Non-utility cost of revenues, including natural gas 2   3 1  
Operation and maintenance 715 678 1,462 1,387  
Depreciation and amortization 370 386 733 749  
Taxes other than income taxes 140 141 294 285  
Interest expense 209 227 454 438  
Income tax expense (benefit) 55 33 136 111  
Interest income (14) (10) (21) (17)  
Other expense (income), net (31) (11) 2 (27)  
Net income (loss) 198 228 495 578  
Operating Segments | Electric          
Segment Reporting Information [Line Items]          
Revenues from external customers 1,191 1,207 2,257 2,256  
Intersegment revenues 0   0    
Utility natural gas, fuel and purchased power 65 50 139 93  
Non-utility cost of revenues, including natural gas 0   0 0  
Operation and maintenance 523 497 1,007 972  
Depreciation and amortization 230 237 440 463  
Taxes other than income taxes 80 77 158 155  
Interest expense 106 97 207 188  
Income tax expense (benefit) 41 47 66 78  
Interest income (7) (6) (11) (11)  
Other expense (income), net (18) (7) (28) (18)  
Net income (loss) 171 215 279 336  
Expenditures for Long-lived Assets     1,716 951  
Total Assets 25,231   25,231   23,936
Operating Segments | Natural Gas          
Segment Reporting Information [Line Items]          
Revenues from external customers 750 695 2,602 2,265  
Intersegment revenues 1   2    
Utility natural gas, fuel and purchased power 236 183 1,169 927  
Non-utility cost of revenues, including natural gas 2   3 1  
Operation and maintenance 195 189 460 423  
Depreciation and amortization 137 142 284 274  
Taxes other than income taxes 56 61 130 126  
Interest expense 43 61 102 112  
Income tax expense (benefit) 11 16 116 79  
Interest income (10) (1) (10) (1)  
Other expense (income), net (5) (3) 36 (6)  
Net income (loss) 86 47 314 330  
Expenditures for Long-lived Assets     696 712  
Total Assets 17,090   17,090   18,583
Operating Segments | Corporate and Other          
Segment Reporting Information [Line Items]          
Revenues from external customers 3 3 5 4  
Intersegment revenues 0   0    
Utility natural gas, fuel and purchased power 0 0 0 0  
Non-utility cost of revenues, including natural gas 0   0 0  
Operation and maintenance (3) (8) (5) (8)  
Depreciation and amortization 3 7 9 12  
Taxes other than income taxes 4 3 6 4  
Interest expense 60 69 145 138  
Income tax expense (benefit) 3 (30) (46) (46)  
Interest income 3 (3) 0 (5)  
Other expense (income), net (8) (1) (6) (3)  
Net income (loss) (59) (34) (98) (88)  
Expenditures for Long-lived Assets     18 7  
Total Assets 1,778   1,778   $ 1,249
Eliminations          
Segment Reporting Information [Line Items]          
Revenues from external customers 0 0 0 0  
Intersegment revenues (1)   (2)    
Utility natural gas, fuel and purchased power (1) 0 (2) 0  
Non-utility cost of revenues, including natural gas 0   0 0  
Operation and maintenance 0 0 0 0  
Depreciation and amortization 0 0 0 0  
Taxes other than income taxes 0 0 0 0  
Interest expense (14) (10) (21) (17)  
Income tax expense (benefit) 0 0 0 0  
Interest income (14) (10) (21) (17)  
Other expense (income), net 0 0 0 0  
Net income (loss) $ 0 $ 0 $ 0 $ 0