CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY - USD ($) $ in Millions	Total	Common stock, without par value	Retained earnings	Accumulated other comprehensive income (loss)	Treasury stock	Total UGI stockholders’ equity	Noncontrolling interests	Cumulative Effect Period Of Adoption Adjustment Retained earnings
Balance, beginning of period at Sep. 30, 2018		$ 1,200.8	$ 2,610.7	$ (110.4)	$ (19.7)		$ 418.6	$ (7.1)
Increase (Decrease) in Stockholders' Equity
Common Stock issued in connection with employee and director plans, net of tax withheld		9.4
Equity-based compensation expense		8.8
Other							0.3
Reclassification of stranded income tax effects related to TCJA	$ (6.6)		6.6	(6.6)
Losses on common stock transactions in connection with employee and director plans			(11.1)
Net income (loss)	485.2		309.6				175.6
Cash dividends on UGI Common Stock ($0.325, $0.260, $0.650, and $0.520, respectively)			(90.5)
Net losses on derivative instruments				(2.7)
Reclassification of net losses on derivative instruments				0.7
Benefit plans	0.6			0.6
Foreign currency adjustments	(42.4)			(42.4)
Common Stock issued in connection with employee and director plans, net of tax withheld					16.0
Repurchases of UGI Common Stock					(16.9)
Reacquired UGI Common Stock - employee and director plans					(2.8)
Dividends and distributions							(131.5)
Balance, end of period at Mar. 31, 2019	4,316.0	1,219.0	2,818.2	(160.8)	(23.4)	$ 3,853.0	463.0
Balance, beginning of period at Dec. 31, 2018		1,206.5	2,620.8	(133.1)	(24.8)		377.2
Increase (Decrease) in Stockholders' Equity
Common Stock issued in connection with employee and director plans, net of tax withheld		5.7
Equity-based compensation expense		6.8
Other							0.3
Losses on common stock transactions in connection with employee and director plans			(2.8)
Net income (loss)	396.7		245.4				151.3
Cash dividends on UGI Common Stock ($0.325, $0.260, $0.650, and $0.520, respectively)			(45.2)
Net losses on derivative instruments				(1.2)
Benefit plans	0.3			0.3
Foreign currency adjustments	(26.8)			(26.8)
Common Stock issued in connection with employee and director plans, net of tax withheld					3.8
Reacquired UGI Common Stock - employee and director plans					(2.4)
Dividends and distributions							(65.8)
Balance, end of period at Mar. 31, 2019	4,316.0	1,219.0	2,818.2	(160.8)	(23.4)	3,853.0	463.0
Balance, beginning of period at Sep. 30, 2019	3,827.2	1,396.9	2,653.1	(216.6)	(15.9)		9.7
Increase (Decrease) in Stockholders' Equity
Common Stock issued in connection with employee and director plans, net of tax withheld		1.7
Equity-based compensation expense		10.7
Other		(0.7)	1.0		1.9		(0.7)
Losses on common stock transactions in connection with employee and director plans			(2.7)
Net income (loss)	437.6		437.5				0.1
Cash dividends on UGI Common Stock ($0.325, $0.260, $0.650, and $0.520, respectively)			(135.6)
Net losses on derivative instruments	(30.0)			(30.0)
Reclassification of net losses on derivative instruments	1.3			1.3
Benefit plans	1.3			1.3
Foreign currency adjustments	14.3			14.3
Common Stock issued in connection with employee and director plans, net of tax withheld					4.4
Repurchases of UGI Common Stock					(38.3)
Balance, end of period at Mar. 31, 2020	4,089.6	1,408.6	2,953.3	(229.7)	(51.7)	4,080.5	9.1
Balance, beginning of period at Dec. 31, 2019		1,398.4	2,797.5	(163.1)	(37.4)		9.2
Increase (Decrease) in Stockholders' Equity
Common Stock issued in connection with employee and director plans, net of tax withheld		1.4
Equity-based compensation expense		8.8
Other					1.9		(0.2)
Losses on common stock transactions in connection with employee and director plans			(2.0)
Net income (loss)	225.6		225.5				0.1
Cash dividends on UGI Common Stock ($0.325, $0.260, $0.650, and $0.520, respectively)			(67.7)
Net losses on derivative instruments	(35.6)			(35.6)
Reclassification of net losses on derivative instruments	0.6			0.6
Benefit plans	1.1			1.1
Foreign currency adjustments	(32.7)			(32.7)
Common Stock issued in connection with employee and director plans, net of tax withheld					3.3
Repurchases of UGI Common Stock					(15.7)
Balance, end of period at Mar. 31, 2020	$ 4,089.6	$ 1,408.6	$ 2,953.3	$ (229.7)	$ (51.7)	$ 4,080.5	$ 9.1