v3.26.1
Risk Management (Details) - USD ($)
3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Dec. 31, 2025
Price Risk Derivatives [Line Items]          
Net gain or (loss) recognized in the statement of income offset by regulatory accounting $ 22,000,000 $ 16,000,000 $ 14,000,000 $ 62,000,000  
Margin deposit assets 0   0    
Aggregate fair value of derivative instruments 205,000,000   205,000,000    
Aggregate fair value in collateral 68,000,000   68,000,000    
Aggregate fair value in cash 56,000,000   56,000,000    
Aggregate fair value in letters of credit 12,000,000   12,000,000    
Collateral aggregate fair value 144,000,000   144,000,000    
Letters of credit 5,000,000   5,000,000    
Cash 29,000,000   29,000,000   $ 21,000,000
Letters of Credit Outstanding, Amount 126,000,000   126,000,000    
Gross amounts included as price risk management liabilities 37,000,000   37,000,000   41,000,000
Right to reclaim cash collateral 13,000,000   13,000,000   $ 14,000,000
Derivative asset amount offset against collateral $ 34,000,000   $ 34,000,000