v3.26.3
Segment Reporting (Details) - USD ($)
$ in Millions
 3 Months Ended 9 Months Ended
Sep. 30, 2026
Sep. 30, 2025
Sep. 30, 2026
Sep. 30, 2025
Segment Reporting [Line Items]        
Electric fuel and purchased power $ 216 $ 208 $ 432 $ 582
Operating and maintenance expenses 99 86 270 257
Utilities Operating Expense, Depreciation and Amortization 128 118 372 345
Other income, net 7 4 10 8
Interest and Debt Expense 58 45 148 133
Income tax expense (benefit) 9 20 (35) (17)
Net income $ 216 160 $ 423 320
Number Of Reportable Segments, Disclosed By Definition, Flag true   true  
Total revenues | Regulated Electric Segment        
Segment Reporting [Line Items]        
Regulated Operating Revenue, Electric $ 738 655 $ 1,657 1,684
Electric fuel and purchased power 216 208 432 582
Operating and maintenance expenses 99 86 270 257
Utilities Operating Expense, Depreciation and Amortization 128 118 372 345
Other income, net 12 18 47 64
Interest and Debt Expense 58 45 148 133
Income tax expense (benefit) 9 20 (35) (17)
Net income $ 216 $ 160 $ 423 $ 320