v3.26.1
Fair Value of Financial Instruments Schedule of Fair Value (Details) - USD ($)
$ in Millions
Jun. 30, 2026
Dec. 31, 2025
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Cash and Cash Equivalents, Fair Value Disclosure $ 0 $ 59
Domestic government, Debt securities 15 25
Corporate debt securities held in decommissioning trust assets 22 10
Money market funds 9 7
Debt securities - domestic government 5 1
Money market funds 1  
Electricity 44 30
Natural gas 2 3
Financial Instruments, Owned, at Fair Value 16 14
Assets, Fair Value Disclosure 105 142
Liabilities from price risk management activities: [Abstract]    
Electricity 52 50
Natural gas 154 164
Liabilities, Fair Value Disclosure 206 214
Portion at Other than Fair Value Measurement    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Money market funds 7 7
Fair Value, Inputs, Level 1 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Cash and Cash Equivalents, Fair Value Disclosure 0 59
Domestic government, Debt securities 8 14
Corporate debt securities held in decommissioning trust assets 0 0
Money market funds 0 0
Debt securities - domestic government 5 1
Money market funds 0  
Electricity 0 0
Natural gas 0 0
Financial Instruments, Owned, at Fair Value 13 74
Liabilities from price risk management activities: [Abstract]    
Electricity 0 0
Natural gas 0 0
Liabilities, Fair Value Disclosure 0 0
Fair Value, Inputs, Level 1 [Member] | Portion at Other than Fair Value Measurement    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Money market funds 0 0
Fair Value, Inputs, Level 2 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Cash and Cash Equivalents, Fair Value Disclosure 0 0
Domestic government, Debt securities 7 11
Corporate debt securities held in decommissioning trust assets 22 10
Money market funds 0 0
Debt securities - domestic government 0 0
Money market funds 1  
Electricity 39 29
Natural gas 2 3
Financial Instruments, Owned, at Fair Value 71 53
Liabilities from price risk management activities: [Abstract]    
Electricity 9 13
Natural gas 143 160
Liabilities, Fair Value Disclosure 152 173
Fair Value, Inputs, Level 2 [Member] | Portion at Other than Fair Value Measurement    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Money market funds 0 0
Fair Value, Inputs, Level 3 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Cash and Cash Equivalents, Fair Value Disclosure 0 0
Domestic government, Debt securities 0 0
Corporate debt securities held in decommissioning trust assets 0 0
Money market funds 0 0
Debt securities - domestic government 0 0
Money market funds 0  
Electricity 5 1
Natural gas 0 0
Financial Instruments, Owned, at Fair Value 5 1
Liabilities from price risk management activities: [Abstract]    
Electricity 43 37
Natural gas 11 4
Liabilities, Fair Value Disclosure 54 41
Fair Value, Inputs, Level 3 [Member] | Portion at Other than Fair Value Measurement    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Money market funds 0 0
Non Qualified Benefit Plans [Member]    
Liabilities from price risk management activities: [Abstract]    
Insurance contracts, at cash surrender value $ 32 $ 35