v3.25.1
Revenue from Contracts with Customers - Narrative (Details) - USD ($)
$ in Millions
6 Months Ended
Mar. 31, 2025
Mar. 31, 2024
Sep. 30, 2024
Disaggregation of Revenue [Line Items]      
Contract liabilities $ 99 $ 126 $ 140
Revenue recognized 95 $ 114  
Midstream & Marketing      
Disaggregation of Revenue [Line Items]      
Expected revenue 2,100    
Utilities      
Disaggregation of Revenue [Line Items]      
Expected revenue $ 200