v3.26.1
Fair Value Measurements - PAC (Details) - USD ($)
$ in Millions
Jun. 30, 2026
Dec. 31, 2025
Recurring    
Assets:    
Derivative asset, offset $ (6) $ (8)
Assets, fair value 6,393 3,566
Liabilities:    
Derivative liability, offset 59 84
Derivative liability (158) (157)
Cash collateral receivable 53 76
Recurring | Money market mutual funds    
Assets:    
Money market mutual funds 3,613 1,469
Recurring | Level 1    
Assets:    
Assets, fair value 5,295 2,648
Liabilities:    
Derivative liability (13) (13)
Recurring | Level 1 | Money market mutual funds    
Assets:    
Money market mutual funds 3,613 1,469
Recurring | Level 2    
Assets:    
Assets, fair value 1,088 916
Liabilities:    
Derivative liability (136) (172)
Recurring | Level 2 | Money market mutual funds    
Assets:    
Money market mutual funds 0 0
Recurring | Level 3    
Assets:    
Assets, fair value 16 10
Liabilities:    
Derivative liability (68) (56)
Recurring | Level 3 | Money market mutual funds    
Assets:    
Money market mutual funds 0 0
Commodity derivatives | Recurring    
Assets:    
Derivative asset, offset (6) (8)
Derivative asset 41 41
Liabilities:    
Derivative liability, offset 58 83
Derivative liability (157) (155)
Commodity derivatives | Recurring | Level 1    
Assets:    
Derivative asset, gross 0 0
Liabilities:    
Derivative liability, gross (13) (13)
Commodity derivatives | Recurring | Level 2    
Assets:    
Derivative asset, gross 44 47
Liabilities:    
Derivative liability, gross (134) (169)
Commodity derivatives | Recurring | Level 3    
Assets:    
Derivative asset, gross 3 2
Liabilities:    
Derivative liability, gross (68) (56)
PAC | Recurring    
Assets:    
Equity securities 24 28
Assets, fair value 2,339 117
PAC | Recurring | U.S. government obligations    
Assets:    
Debt securities 493  
PAC | Recurring | Money market mutual funds    
Assets:    
Money market mutual funds 1,820 84
PAC | Recurring | Level 1    
Assets:    
Equity securities 24 28
Assets, fair value 2,337 112
PAC | Recurring | Level 1 | U.S. government obligations    
Assets:    
Debt securities 493  
PAC | Recurring | Level 1 | Money market mutual funds    
Assets:    
Money market mutual funds 1,820 84
PAC | Recurring | Level 2    
Assets:    
Equity securities 0 0
Assets, fair value 5 10
PAC | Recurring | Level 2 | U.S. government obligations    
Assets:    
Debt securities 0  
PAC | Recurring | Level 2 | Money market mutual funds    
Assets:    
Money market mutual funds 0 0
PAC | Recurring | Level 3    
Assets:    
Equity securities 0 0
Assets, fair value 0 0
PAC | Recurring | Level 3 | U.S. government obligations    
Assets:    
Debt securities 0  
PAC | Recurring | Level 3 | Money market mutual funds    
Assets:    
Money market mutual funds 0 0
PAC | Commodity derivatives    
Liabilities:    
Cash collateral receivable 49 71
PAC | Commodity derivatives | Recurring    
Assets:    
Derivative asset, offset (3) (5)
Derivative asset 2 5
Liabilities:    
Derivative liability, offset 52 76
Derivative liability (55) (71)
Cash collateral receivable 49 71
PAC | Commodity derivatives | Recurring | Level 1    
Assets:    
Derivative asset, gross 0 0
Liabilities:    
Derivative liability, gross 0 0
PAC | Commodity derivatives | Recurring | Level 2    
Assets:    
Derivative asset, gross 5 10
Liabilities:    
Derivative liability, gross (107) (147)
PAC | Commodity derivatives | Recurring | Level 3    
Assets:    
Derivative asset, gross 0 0
Liabilities:    
Derivative liability, gross $ 0 $ 0