Condensed Consolidated Balance Sheets (unaudited) (Parenthetical) - USD ($) $ in Millions	Jun. 30, 2017	Sep. 30, 2016	Jun. 30, 2016
Statement of Financial Position [Abstract]
Accounts receivable, allowances for doubtful accounts	$ 33.0	$ 27.3	$ 32.1
Property, plant and equipment, accumulated depreciation and amortization	$ 3,337.5	$ 3,107.3	$ 3,037.9
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	173,960,691	173,894,141	173,875,641