Utility Regulatory Assets and Liabilities and Regulatory Matters - Narrative (Details) - USD ($)	Oct. 08, 2020	Jan. 28, 2020	Oct. 11, 2019	Jan. 28, 2019	Dec. 31, 2020	Sep. 30, 2020	Dec. 31, 2019
UGI Gas
Regulatory Assets
Public utilities, tax benefits, effective period			12 months
UGI Gas | PAPUC
Regulatory Assets
Public utilities, requested rate increase (decrease), amount		$ 75,000,000		$ 71,000,000
Public utilities, approved rate increase (decrease), amount	$ 20,000,000		$ 30,000,000
Property, plant and equipment, net threshold	$ 2,875,000,000
Amortization period	10 years
Tax benefit to be returned, period			5 years
Tax benefit to be returned				$ 24,000,000
UGI Gas | PAPUC | Beginning January 1, 2021
Regulatory Assets
Public utilities, approved rate increase (decrease), amount	$ 10,000,000
UGI Gas | PAPUC | Beginning July 1, 2021
Regulatory Assets
Public utilities, approved rate increase (decrease), amount	$ 10,000,000
Gas Utility
Regulatory Assets
Fair value of unrealized gains (losses)					$ (1,000,000)	$ 8,000,000	$ (3,000,000)