Segment Information - Schedule of Segment Reporting Information (Details) - USD ($) $ in Millions		3 Months Ended
		Dec. 31, 2015	Dec. 31, 2014		Sep. 30, 2015
Segment Reporting Information
Revenues		$ 1,606.6	$ 2,004.6	[1]
Cost of sales		734.0	1,404.6	[1]
Segment profit:
Operating income (loss)		305.5	83.3	[1]
Loss from equity investees		(0.1)	(1.0)	[1]
Interest expense		(57.9)	(59.0)	[1]
Income before income taxes		247.5	23.3	[1]
Noncontrolling interests’ net income (loss)		53.3	(33.9)	[1]
Depreciation and amortization		100.6	91.0	[1]
Capital expenditures		132.9	123.5	[1]
Total assets		10,780.4	10,430.0	[1]	$ 10,546.6
Short-term borrowings		456.8	458.5	[1]	189.9
Goodwill		2,965.1	2,806.8	[1]	$ 2,953.4
AmeriGas Propane
Segment profit:
Operating income (loss)		129.6	139.7
Partnership Adjusted EBITDA		177.7	188.5
Depreciation and amortization		49.2	49.4
Intersegment Eliminations
Segment Reporting Information
Revenues	[2]	(45.4)	(67.7)	[1]
Cost of sales	[2]	(44.5)	(67.0)	[1]
Segment profit:
Operating income (loss)		0.1	0.0	[1]
Loss from equity investees		0.0	0.0	[1]
Interest expense		0.0	0.0	[1]
Income before income taxes		0.1	0.0	[1]
Noncontrolling interests’ net income (loss)		0.0	0.0	[1]
Depreciation and amortization		0.0	0.0	[1]
Capital expenditures		0.0	0.0	[1]
Total assets		(106.2)	(92.7)	[1]
Short-term borrowings		0.0	0.0	[1]
Goodwill		0.0	0.0	[1]
Operating Segments | AmeriGas Propane
Segment Reporting Information
Revenues		644.1	888.8	[1]
Cost of sales		243.2	462.4	[1]
Segment profit:
Operating income (loss)		129.6	139.7	[1]
Loss from equity investees		0.0	0.0	[1]
Interest expense		(41.0)	(41.0)	[1]
Income before income taxes		88.6	98.7	[1]
Partnership Adjusted EBITDA	[3]	177.7	188.5	[1]
Noncontrolling interests’ net income (loss)		57.3	66.8	[1]
Depreciation and amortization		49.2	49.4	[1]
Capital expenditures		28.0	30.4	[1]
Total assets		4,242.6	4,491.0	[1]
Short-term borrowings		182.0	253.0	[1]
Goodwill		1,971.3	1,949.6	[1]
Operating Segments | UGI Utilities
Segment Reporting Information
Revenues		198.0	287.3	[1]
Cost of sales		75.4	143.1	[1]
Segment profit:
Operating income (loss)		48.3	75.6	[1]
Loss from equity investees		0.0	0.0	[1]
Interest expense		(9.5)	(10.6)	[1]
Income before income taxes		38.8	65.0	[1]
Noncontrolling interests’ net income (loss)		0.0	0.0	[1]
Depreciation and amortization		16.7	15.4	[1]
Capital expenditures		61.5	55.0	[1]
Total assets		2,606.3	2,488.6	[1]
Short-term borrowings		217.7	153.5	[1]
Goodwill		182.1	182.1	[1]
Operating Segments | Midstream & Marketing, Energy Services
Segment Reporting Information
Revenues		214.8	314.1	[1]
Cost of sales		151.2	244.6	[1]
Segment profit:
Operating income (loss)		41.3	46.3	[1]
Loss from equity investees		0.0	0.0	[1]
Interest expense		(0.8)	(0.6)	[1]
Income before income taxes		40.5	45.7	[1]
Noncontrolling interests’ net income (loss)		0.0	0.0	[1]
Depreciation and amortization		4.1	3.8	[1]
Capital expenditures		21.9	12.9	[1]
Total assets		721.0	728.8	[1]
Short-term borrowings		56.0	43.0	[1]
Goodwill		11.5	11.8	[1]
Operating Segments | Midstream & Marketing, Electric Generation
Segment Reporting Information
Revenues		14.8	16.5	[1]
Cost of sales		6.0	8.0	[1]
Segment profit:
Operating income (loss)		1.6	(0.7)	[1]
Loss from equity investees		0.0	0.0	[1]
Interest expense		0.0	0.0	[1]
Income before income taxes		1.6	(0.7)	[1]
Noncontrolling interests’ net income (loss)		0.0	0.0	[1]
Depreciation and amortization		3.3	2.7	[1]
Capital expenditures		0.5	6.6	[1]
Total assets		279.0	286.4	[1]
Short-term borrowings		0.0	0.0	[1]
Goodwill		0.0	0.0	[1]
Operating Segments | UGI International, UGI France
Segment Reporting Information
Revenues		408.7	337.9	[1]
Cost of sales		192.6	209.3	[1]
Segment profit:
Operating income (loss)		68.7	38.4	[1]
Loss from equity investees		(0.1)	(1.0)	[1]
Interest expense		(5.6)	(5.6)	[1]
Income before income taxes		63.0	31.8	[1]
Noncontrolling interests’ net income (loss)		0.1	0.1	[1]
Depreciation and amortization		21.6	13.3	[1]
Capital expenditures		16.3	12.1	[1]
Total assets		2,378.9	1,671.5	[1]
Short-term borrowings		1.1	0.0	[1]
Goodwill		700.9	575.9	[1]
Operating Segments | UGI International, Flaga & Other
Segment Reporting Information
Revenues		169.5	224.6	[1]
Cost of sales		110.2	172.6	[1]
Segment profit:
Operating income (loss)		16.4	15.1	[1]
Loss from equity investees		0.0	0.0	[1]
Interest expense		(0.9)	(1.0)	[1]
Income before income taxes		15.5	14.1	[1]
Noncontrolling interests’ net income (loss)		0.0	0.0	[1]
Depreciation and amortization		5.6	6.1	[1]
Capital expenditures		4.7	6.4	[1]
Total assets		534.8	579.0	[1]
Short-term borrowings		0.0	9.0	[1]
Goodwill		99.3	87.4	[1]
Corporate & Other
Segment Reporting Information
Revenues	[4]	2.1	3.1	[1]
Cost of sales	[4]	(0.1)	231.6	[1]
Segment profit:
Operating income (loss)	[4]	(0.5)	(231.1)	[1]
Loss from equity investees	[4]	0.0	0.0	[1]
Interest expense	[4]	(0.1)	(0.2)	[1]
Income before income taxes	[4]	(0.6)	(231.3)	[1]
Noncontrolling interests’ net income (loss)	[4]	(4.1)	(100.8)	[1]
Depreciation and amortization	[4]	0.1	0.3	[1]
Capital expenditures	[4]	0.0	0.1	[1]
Total assets	[4]	124.0	277.4	[1]
Short-term borrowings	[4]	0.0	0.0	[1]
Goodwill	[4]	0.0	0.0	[1]
Gains (losses) on unsettled commodity derivative instruments, net		$ 1.1	$ (229.7)

[1] Certain amounts have been restated to reflect the current-year changes in our segment presentation as described above.

[2] Represents the elimination of intersegment transactions principally among Midstream & Marketing, UGI Utilities and AmeriGas Propane.

[3] The following table provides a reconciliation of Partnership Adjusted EBITDA to AmeriGas Propane operating income: Three Months Ended December 31, 2015 2014Partnership Adjusted EBITDA $177.7 $188.5Depreciation and amortization (49.2) (49.4)Noncontrolling interests (i) 1.1 0.6Operating income $129.6 $139.7(i)Principally represents the General Partner’s 1.01% interest in AmeriGas OLP.

[4] Corporate & Other results principally comprise (1) net expenses of UGI’s captive general liability insurance company, and (2) UGI Corporation’s unallocated corporate and general expenses and interest income. In addition, Corporate & Other results also include the effects of net pre-tax gains and (losses) on commodity derivative instruments not associated with current-period transactions totaling $1.1 and $(229.7) during the three months ended December 31, 2015 and 2014, respectively. Corporate & Other assets principally comprise cash and short-term investments.