v3.26.3
Segments - Segments and Reconciliation (Details) - USD ($)
$ in Millions
 3 Months Ended 9 Months Ended
Sep. 30, 2026
Sep. 30, 2025
Sep. 30, 2026
Sep. 30, 2025
Segment Reporting [Abstract]        
Number of reportable segments not disclosed Flag     operating segment  
Segment Reporting [Line Items]        
Operating revenues $ 1,327 $ 812 $ 3,203 $ 1,832
Operation, maintenance and development expenses 167 131 542 469
Interest expense and other finance charges 148 67 481 203
Capital expenditures 225 65 472 166
Operating Segments | PJM        
Segment Reporting [Line Items]        
Operating revenues 1,319 755 3,169 1,760
Operation, maintenance and development expenses 160 124 520 442
Interest expense and other finance charges 0 0 0 0
Other segment items 475 266 1,108 629
Adjusted EBITDA 684 365 1,541 689
Capital expenditures 76 61 195 156
Operating Segments | Other        
Segment Reporting [Line Items]        
Operating revenues 27 75 68 116
Operation, maintenance and development expenses 7 7 22 27
Interest expense and other finance charges 0 0 0 0
Adjusted EBITDA 6 16 21 24
Capital expenditures 147 3 273 8
Corporate and Eliminations        
Segment Reporting [Line Items]        
Operating revenues (19) (18) (34) (44)
Interest expense and other finance charges 148 67 481 203
Adjusted EBITDA (21) (18) (46) (60)
Capital expenditures $ 2 $ 1 $ 4 $ 2