v3.26.3
Segment Information (Details) - USD ($)
$ in Millions
 3 Months Ended 9 Months Ended
Sep. 30, 2026
Sep. 30, 2025
Sep. 30, 2026
Sep. 30, 2025
Dec. 31, 2025
Segment Reporting [Line Items]          
Electric $ 3,888 $ 3,638 $ 9,604 $ 9,351  
Natural gas 272 264 1,667 1,715  
Revenues Including Intersegment Revenues 4,166 3,910 11,286 11,085  
Electric fuel and purchased power 1,067 1,098 2,764 3,036  
Cost of natural gas sold and transported 58 61 671 708  
Operating and maintenance expenses 759 692 2,125 2,053  
Utilities Operating Expense, Depreciation and Amortization 791 750 2,221 2,200  
Other income, net 62 46 121 121  
Interest and Debt Expense 432 348 1,202 979  
Income tax expense (benefit) 69 8 (38) (113)  
Net income 960 524 2,102 1,451  
Equity Method Investments $ 354   $ 354   $ 285
Number Of Reportable Segments, Disclosed By Definition, Flag true   true    
Operating Segments          
Segment Reporting [Line Items]          
Regulated Operating Revenue $ 4,160 3,902 $ 11,271 11,066  
Electric fuel and purchased power 1,067 1,098 2,764 3,036  
Cost of natural gas sold and transported 58 61 671 708  
Operating and maintenance expenses 746 687 2,088 2,020  
Utilities Operating Expense, Depreciation and Amortization 786 746 2,206 2,189  
Other income, net 174 471 523 882  
Interest and Debt Expense 319 259 903 737  
Income tax expense (benefit) 83 35 (6) (51)  
Net income 933 553 2,137 1,564  
Intersegment Eliminations          
Segment Reporting [Line Items]          
Regulated Operating Revenue 6 8 15 19  
All Other          
Segment Reporting [Line Items]          
Net income 27 (29) (35) (113)  
Equity Method Investments 285   285   204
Regulated Electric Segment          
Segment Reporting [Line Items]          
Revenues Including Intersegment Revenues 3,888 3,638 9,605 9,351  
Regulated Electric Segment | Operating Segments          
Segment Reporting [Line Items]          
Electric 3,888 3,638 9,604 9,351  
Electric fuel and purchased power 1,067 1,098 2,764 3,036  
Cost of natural gas sold and transported 0 0 0 0  
Operating and maintenance expenses 635 582 1,765 1,704  
Utilities Operating Expense, Depreciation and Amortization 673 640 1,872 1,883  
Other income, net 159 443 443 770  
Interest and Debt Expense 285 228 800 645  
Income tax expense (benefit) 107 55 (28) (88)  
Net income 962 592 1,989 1,401  
Regulated Electric Segment | Intersegment Eliminations          
Segment Reporting [Line Items]          
Electric 0 0 1 0  
Regulated Natural Gas Segment          
Segment Reporting [Line Items]          
Revenues Including Intersegment Revenues 278 272 1,681 1,734  
Equity Method Investments 69   69   $ 81
Regulated Natural Gas Segment | Operating Segments          
Segment Reporting [Line Items]          
Natural gas 272 264 1,667 1,715  
Electric fuel and purchased power 0 0 0 0  
Cost of natural gas sold and transported 58 61 671 708  
Operating and maintenance expenses 111 105 323 316  
Utilities Operating Expense, Depreciation and Amortization 113 106 334 306  
Other income, net 15 28 80 112  
Interest and Debt Expense 34 31 103 92  
Income tax expense (benefit) (24) (20) 22 37  
Net income (29) (39) 148 163  
Regulated Natural Gas Segment | Intersegment Eliminations          
Segment Reporting [Line Items]          
Natural gas $ 6 $ 8 $ 14 $ 19