Revenue from Contracts with Customers - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022
Disaggregation of Revenue [Line Items]
Contract liabilities	$ 140	$ 158
Contract liabilities, recognized revenue	120	$ 127	$ 119
Midstream & Marketing
Disaggregation of Revenue [Line Items]
Remaining performance obligations	2,300
UGI Utilities, Inc.
Disaggregation of Revenue [Line Items]
Remaining performance obligations	$ 200
Natural Gas Transportation and Gathering Services
Disaggregation of Revenue [Line Items]
Term of contract with customer (up to)	30 years
Storage Services
Disaggregation of Revenue [Line Items]
Term of contract with customer (up to)	1 year
Natural Gas
Disaggregation of Revenue [Line Items]
Term of contract with customer (up to)	15 years