Utility Regulatory Assets and Liabilities and Regulatory Matters (Details) - UGI Utilities - USD ($) $ in Millions	Dec. 31, 2020	Sep. 30, 2020	Dec. 31, 2019
Regulatory Assets
Regulatory assets	$ 395.0	$ 397.0	$ 391.0
Regulatory Liabilities
Regulatory liabilities	346.0	353.0	351.0
Postretirement benefit overcollections
Regulatory Liabilities
Regulatory liabilities	13.0	13.0	14.0
Deferred fuel and power refunds
Regulatory Liabilities
Regulatory liabilities	24.0	29.0	6.0
State tax benefits — distribution system repairs
Regulatory Liabilities
Regulatory liabilities	28.0	28.0	26.0
PAPUC temporary rates order
Regulatory Liabilities
Regulatory liabilities	5.0	7.0	25.0
Excess federal deferred income taxes
Regulatory Liabilities
Regulatory liabilities	272.0	274.0	278.0
Other
Regulatory Liabilities
Regulatory liabilities	4.0	2.0	2.0
Income taxes recoverable
Regulatory Assets
Regulatory assets	126.0	124.0	121.0
Underfunded pension and postretirement plans
Regulatory Assets
Regulatory assets	172.0	175.0	175.0
Environmental costs
Regulatory Assets
Regulatory assets	59.0	61.0	58.0
Removal costs, net
Regulatory Assets
Regulatory assets	24.0	26.0	27.0
Other
Regulatory Assets
Regulatory assets	$ 14.0	$ 11.0	$ 10.0

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