Condensed Consolidated Statements of Comprehensive Income (unaudited) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2018	Mar. 31, 2017
Statement of Comprehensive Income [Abstract]
Net income including noncontrolling interests	$ 407.7	$ 311.8	$ 841.9	$ 602.7
Other comprehensive income (loss):
Net (losses) gains on derivative instruments (net of tax of $0.7, $0.3, $0.9 and $(5.7), respectively)	(1.6)	(0.5)	(2.0)	11.8
Reclassifications of net losses (gains) on derivative instruments (net of tax of $(1.5), $2.5, $(1.4) and $4.6, respectively)	2.8	(5.4)	2.4	(9.9)
Foreign currency adjustments	35.9	17.8	58.2	(53.1)
Benefit plans (net of tax of $(0.1), $(0.3), $(0.3) and $(0.9), respectively)	0.3	0.4	0.7	1.4
Other comprehensive income (loss)	37.4	12.3	59.3	(49.8)
Comprehensive income including noncontrolling interests	445.1	324.1	901.2	552.9
Deduct comprehensive income attributable to noncontrolling interests, principally in AmeriGas Partners	(131.7)	(91.9)	(200.0)	(152.1)
Comprehensive income attributable to UGI Corporation	$ 313.4	$ 232.2	$ 701.2	$ 400.8