v3.25.2
Risk Management Activities and Derivative Transactions Derivatives Under FTP (Details) - USD ($)
$ in Millions
Jun. 30, 2025
Sep. 30, 2024
Derivative    
Forward Contract Derivative Asset, at Fair Value $ 18 $ 11
Fair value 8 64
Commodity Contract under FHP    
Derivative    
Fair value (1) (161)
Fair Value, Inputs, Level 2    
Derivative    
Forward Contract Derivative Asset, at Fair Value $ 18 $ 11