Goodwill and Intangible Assets - Narrative (Details) - USD ($)	3 Months Ended		12 Months Ended
	Sep. 30, 2023	Jun. 30, 2023	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2021	May 31, 2023
Goodwill [Line Items]
Impairment of goodwill			$ 656,000,000	$ 0	$ 0
Goodwill	$ 3,027,000,000		3,027,000,000	3,612,000,000	3,770,000,000
Impairment of customer relationship intangible					20,000,000
Amortization expense of intangible assets			56,000,000	61,000,000	76,000,000
Fiscal 2024	53,000,000		53,000,000
Fiscal 2025	51,000,000		51,000,000
Fiscal 2026	50,000,000		50,000,000
Fiscal 2027	27,000,000		27,000,000
Fiscal 2028	18,000,000		18,000,000
Customer relationships
Goodwill [Line Items]
Impairment of customer relationship intangible			10,000,000
AmeriGas Propane
Goodwill [Line Items]
Impairment of goodwill	656,000,000	$ 656,000,000	656,000,000
Goodwill	$ 1,348,000,000		$ 1,348,000,000	$ 2,004,000,000	$ 2,004,000,000
Senior Notes Due 2028 | UGI Utilities Senior Notes: | AmeriGas Partners And AmeriGas Finance Corp.
Goodwill [Line Items]
Principal amount						$ 500,000,000
Interest rate						9.375%