Condensed Consolidated Balance Sheets (unaudited) (Parenthetical) - USD ($) $ in Millions	Mar. 31, 2017	Sep. 30, 2016	Mar. 31, 2016
Statement of Financial Position [Abstract]
Accounts receivable, allowances for doubtful accounts	$ 34.7	$ 27.3	$ 34.1
Property, plant and equipment, accumulated depreciation and amortization	$ 3,221.9	$ 3,107.3	$ 2,987.1
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	173,949,791	173,894,141	173,842,891