Utility Regulatory Assets and Liabilities and Regulatory Matters - Narrative (Details) - USD ($)									12 Months Ended
	Nov. 09, 2021	Feb. 08, 2021	Oct. 08, 2020	Jan. 28, 2020	Oct. 11, 2019	Jan. 28, 2019	Oct. 27, 2018	Oct. 19, 2016	Sep. 30, 2021	Sep. 30, 2020
Regulatory Assets [Line Items]
Regulatory asset, amortization period							20 years
UGI Gas
Regulatory Assets [Line Items]
Effective period						12 months
Pennsylvania Public Utility Commission | UGI Gas
Regulatory Assets [Line Items]
Regulatory asset, amortization period			10 years
Requested rate increase		$ 9,000,000		$ 75,000,000		$ 71,000,000
Approved rate increase, amount			$ 20,000,000		$ 30,000,000
Property, plant and equipment, net threshold			2,875,000,000
Energy Efficiency and Conservation and Growth extension tariff, extension term					5 years
Tax benefit to be returned						$ 24,000,000
Pennsylvania Public Utility Commission | UGI Gas | Subsequent Event
Regulatory Assets [Line Items]
Approved rate increase, amount	$ 6,000,000
Pennsylvania Public Utility Commission | UGI Gas | Beginning January 1, 2021
Regulatory Assets [Line Items]
Approved rate increase, amount			10,000,000
Pennsylvania Public Utility Commission | UGI Gas | Beginning July 1, 2021
Regulatory Assets [Line Items]
Approved rate increase, amount			$ 10,000,000
Postretirement benefit overcollections
Regulatory Assets [Line Items]
Regulatory liability, amortization period								10 years
Regulated natural gas utilities
Regulatory Assets [Line Items]
Fair value of unrealized gains (losses)									$ 35,000,000	$ 8,000,000
Minimum
Regulatory Assets [Line Items]
Average remaining depreciable lives of the associated property									1 year
Maximum
Regulatory Assets [Line Items]
Average remaining depreciable lives of the associated property									65 years
Maximum | Removal Costs, Net
Regulatory Assets [Line Items]
Regulatory asset, amortization period									5 years