v3.25.3
Fair Value Measurements - Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($)
$ in Millions
Sep. 30, 2025
Dec. 31, 2024
Assets    
Total $ 824 $ 3,021
Liabilities    
Total 395 39
Interest rate swaps    
Assets    
Derivative assets 429 1,609
Liabilities    
Derivative liabilities 259 3
Natural gas supply contracts    
Assets    
Derivative assets 48 39
Liabilities    
Derivative liabilities 136 36
Level 1    
Assets    
Total 347 1,373
Liabilities    
Total 0 0
Level 1 | Interest rate swaps    
Assets    
Derivative assets 0 0
Liabilities    
Derivative liabilities 0 0
Level 1 | Natural gas supply contracts    
Assets    
Derivative assets 0 0
Liabilities    
Derivative liabilities 0 0
Level 2    
Assets    
Total 430 1,609
Liabilities    
Total 274 6
Level 2 | Interest rate swaps    
Assets    
Derivative assets 429 1,609
Liabilities    
Derivative liabilities 259 3
Level 2 | Natural gas supply contracts    
Assets    
Derivative assets 1 0
Liabilities    
Derivative liabilities 15 3
Level 3    
Assets    
Total 47 39
Liabilities    
Total 121 33
Level 3 | Interest rate swaps    
Assets    
Derivative assets 0 0
Liabilities    
Derivative liabilities 0 0
Level 3 | Natural gas supply contracts    
Assets    
Derivative assets 47 39
Liabilities    
Derivative liabilities 121 33
Money market funds    
Assets    
Money market funds 347 1,373
Money market funds | Level 1    
Assets    
Money market funds 347 1,373
Money market funds | Level 2    
Assets    
Money market funds 0 0
Money market funds | Level 3    
Assets    
Money market funds $ 0 $ 0