CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Millions	Jun. 30, 2020	Sep. 30, 2019	Jun. 30, 2019
Statement of Financial Position [Abstract]
Allowance for doubtful accounts	$ 41.7	$ 31.6	$ 42.8
Accumulated depreciation	$ 3,599.7	$ 3,385.2	$ 3,353.0
UGI Common Stock, without par value, shares authorized	450,000,000	450,000,000	450,000,000
UGI Common Stock, without par value, shares issued	209,504,994	209,304,129	174,678,299