Condensed Consolidated Statements of Comprehensive Income (unaudited) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Statement of Comprehensive Income [Abstract]
Net (loss) income including noncontrolling interests	$ (11.7)	$ (62.2)	$ 830.2	$ 540.5
Other comprehensive income (loss):
Net gains (losses) on derivative instruments (net of tax of $(1.5), $3.4, $(0.6) and $(2.3), respectively)	3.7	(6.6)	1.7	5.2
Reclassifications of net losses (gains) on derivative instruments (net of tax of $(0.2), $(0.2), $(1.6) and $4.4, respectively)	0.2	(0.2)	2.6	(10.1)
Foreign currency adjustments	(82.0)	75.5	(23.8)	22.4
Benefit plans (net of tax of $(0.2), $0.0, $(0.5) and $(0.9), respectively)	0.6	(0.1)	1.3	1.3
Other comprehensive (loss) income	(77.5)	68.6	(18.2)	18.8
Comprehensive (loss) income including noncontrolling interests	(89.2)	6.4	812.0	559.3
Add comprehensive loss (deduct comprehensive income) attributable to noncontrolling interests, principally in AmeriGas Partners	64.1	43.2	(135.9)	(108.9)
Comprehensive (loss) income attributable to UGI Corporation	$ (25.1)	$ 49.6	$ 676.1	$ 450.4