v3.26.1
Fair Value of Financial Instruments - Reconciliation of Level 3 Financial Instruments (Details) - Level 3 - Derivatives - USD ($)
$ in Millions
3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Beginning balance $ 30 $ 49 $ 110 $ 39
Total (losses)/gains realized/unrealized included in earnings (32) 22 (134) 34
Purchases 10 37 22 37
Transfers into Level 3 (1) 63 0 63
Transfers out of Level 3 (1) 1 3 (1)
Ending balance 6 81 6 81
(Losses)/gains for the period included in earnings attributable to the change in unrealized gains or losses relating to assets or liabilities still held as of period end (31) 5 (104) 47
LS Power Portfolio        
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Contracts added from acquisitions 0 0 5 0
Texas Generation Portfolio        
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Contracts added from acquisitions $ 0 $ (91) $ 0 $ (91)