v3.26.1
Summary of Significant Accounting Policies - Narrative (Details) - USD ($)
$ in Millions
Jun. 30, 2026
Sep. 30, 2025
Jun. 30, 2025
Segment Reporting [Line Items]      
Goodwill $ 2,780 $ 2,852 $ 2,888
AmeriGas Propane      
Segment Reporting [Line Items]      
Percentage of fair value exceeding carrying value 25.00%    
Goodwill $ 1,100