Segment Information - Schedule of Segment Reporting Information (Details) - USD ($) $ in Millions		3 Months Ended			9 Months Ended
		Jun. 30, 2015		Jun. 30, 2014	Jun. 30, 2015		Jun. 30, 2014	Sep. 30, 2014
Segment Reporting Information
Revenues		$ 1,148.1		$ 1,486.7	$ 5,608.3		$ 6,965.9
Cost of sales		586.4		926.5	3,196.4		4,357.7
Segment profit:
Operating income (loss)		56.1		62.7	841.5		1,015.0
Loss from equity investees		0.0		(0.1)	(1.1)		(0.1)
Interest expense		(67.5)		(60.1)	(184.7)		(178.9)
(Loss) income before income taxes		(11.4)		2.5	655.7		836.0
Noncontrolling interests’ net income (loss)		(25.5)		(33.3)	176.3		235.6
Depreciation and amortization		92.5		90.0	271.5		271.7
Capital expenditures		113.2		102.4	328.1		290.5
Total assets		10,520.0		10,077.7	10,520.0		10,077.7	$ 10,093.0
Short-term borrowings		68.0		96.5	68.0		96.5	210.8
Goodwill		2,927.7		2,885.1	2,927.7		2,885.1	$ 2,833.4
AmeriGas Propane
Segment profit:
Operating income (loss)		0.8		7.2	437.4		471.7
Partnership Adjusted EBITDA		48.9		55.1	579.5		616.5
Depreciation and amortization		48.0		47.8	145.5		149.3
Intersegment Eliminations
Segment Reporting Information
Revenues	[1]	(27.0)		(50.8)	(209.4)		(281.0)
Cost of sales	[1]	(26.4)		(49.6)	(207.4)		(278.0)
Segment profit:
Operating income (loss)		0.0		(0.1)	0.1		0.0
Loss from equity investees		0.0		0.0	0.0		0.0
Interest expense		0.0		0.0	0.0		0.0
(Loss) income before income taxes		0.0		(0.1)	0.1		0.0
Noncontrolling interests’ net income (loss)		0.0		0.0	0.0		0.0
Depreciation and amortization		0.1		0.0	0.0		(0.1)
Capital expenditures		0.0		1.2	0.0		0.0
Total assets		(121.8)		(112.8)	(121.8)		(112.8)
Short-term borrowings		0.0		0.0	0.0		0.0
Goodwill		0.0		0.0	0.0		0.0
Operating Segments
Segment profit:
Derivative, Gain (Loss) on Derivative, Net, And Write-off Of Deferred Debt Issuance Cost		10.3			10.3
Operating Segments | AmeriGas Propane
Segment Reporting Information
Revenues		478.0		613.2	2,467.1		3,152.7
Cost of sales		211.4		340.8	1,179.0		1,809.0
Segment profit:
Operating income (loss)		0.8		7.2	437.4		471.7
Loss from equity investees		0.0		0.0	0.0		0.0
Interest expense		(40.3)		(41.4)	(122.4)		(125.0)
(Loss) income before income taxes		(39.5)		(34.2)	315.0		346.7
Partnership Adjusted EBITDA	[2]	48.9		55.1	579.5		616.5
Noncontrolling interests’ net income (loss)		(36.1)		(31.0)	211.6		237.6
Depreciation and amortization		48.0		47.8	145.5		149.3
Capital expenditures		20.7		29.3	77.9		80.3
Total assets		4,202.6		4,345.8	4,202.6		4,345.8
Short-term borrowings		43.6		92.5	43.6		92.5
Goodwill		1,954.1		1,939.0	1,954.1		1,939.0
Operating Segments | Gas Utility
Segment Reporting Information
Revenues		119.4		128.3	847.9		880.0
Cost of sales		41.3		49.2	426.7		463.5
Segment profit:
Operating income (loss)		15.1		17.1	226.2		233.7
Loss from equity investees		0.0		0.0	0.0		0.0
Interest expense		(9.5)		(9.8)	(29.7)		(26.6)
(Loss) income before income taxes		5.6		7.3	196.5		207.1
Noncontrolling interests’ net income (loss)		0.0		0.0	0.0		0.0
Depreciation and amortization		14.8		13.7	43.6		40.7
Capital expenditures		41.3		35.9	134.0		98.8
Total assets		2,279.0		2,147.4	2,279.0		2,147.4
Short-term borrowings		2.7		0.0	2.7		0.0
Goodwill		182.1		182.1	182.1		182.1
Operating Segments | Midstream & Marketing, Energy Services
Segment Reporting Information
Revenues		169.7		248.3	876.1		1,109.9
Cost of sales		135.9		209.2	666.8		894.2
Segment profit:
Operating income (loss)		17.3		23.5	157.4		166.8
Loss from equity investees		0.0		0.0	0.0		0.0
Interest expense		(0.5)		(0.5)	(1.6)		(2.5)
(Loss) income before income taxes		16.8		23.0	155.8		164.3
Noncontrolling interests’ net income (loss)		0.0		0.0	0.0		0.0
Depreciation and amortization		3.7		3.3	10.9		9.1
Capital expenditures		27.5		11.2	46.2		41.3
Total assets		629.9		542.7	629.9		542.7
Short-term borrowings		20.0		0.0	20.0		0.0
Goodwill		5.6		5.6	5.6		5.6
Operating Segments | Midstream & Marketing, Electric Generation
Segment Reporting Information
Revenues		16.2		20.5	57.5		66.4
Cost of sales		7.7		10.5	25.1		30.5
Segment profit:
Operating income (loss)		1.3		2.6	8.6		16.9
Loss from equity investees		0.0		0.0	0.0		0.0
Interest expense		0.0		0.0	0.0		0.0
(Loss) income before income taxes		1.3		2.6	8.6		16.9
Noncontrolling interests’ net income (loss)		0.0		0.0	0.0		0.0
Depreciation and amortization		3.2		2.7	9.2		8.0
Capital expenditures		1.1		1.9	10.0		13.0
Total assets		277.6		279.1	277.6		279.1
Short-term borrowings		0.0		0.0	0.0		0.0
Goodwill		0.0		0.0	0.0		0.0
Operating Segments | UGI International, Antargaz
Segment Reporting Information
Revenues		196.1		249.2	881.2		1,086.5
Cost of sales		107.9		164.1	517.5		713.3
Segment profit:
Operating income (loss)		(9.1)		(1.4)	82.5		94.7
Loss from equity investees		0.0		(0.1)	(1.1)		(0.1)
Interest expense		(15.7)	[3]	(6.3)	(26.2)	[3]	(19.1)
(Loss) income before income taxes		(24.8)		(7.8)	55.2		75.5
Noncontrolling interests’ net income (loss)		(0.2)		(0.3)	0.2		0.0
Depreciation and amortization		15.2		14.6	40.3		39.9
Capital expenditures		17.2		15.6	38.9		36.7
Total assets		2,377.9		1,784.2	2,377.9		1,784.2
Short-term borrowings		0.0		0.0	0.0		0.0
Goodwill		699.8		651.7	699.8		651.7
Operating Segments | UGI International, Flaga & Other
Segment Reporting Information
Revenues		150.7		232.3	548.2		802.8
Cost of sales		101.8		180.7	397.7		635.1
Segment profit:
Operating income (loss)		8.8		8.2	35.4		32.8
Loss from equity investees		0.0		0.0	0.0		0.0
Interest expense		(0.9)		(1.4)	(2.8)		(3.8)
(Loss) income before income taxes		7.9		6.8	32.6		29.0
Noncontrolling interests’ net income (loss)		0.0		0.0	0.0		0.0
Depreciation and amortization		5.9		6.2	17.2		20.0
Capital expenditures		3.3		4.8	15.1		13.6
Total assets		534.5		650.6	534.5		650.6
Short-term borrowings		1.7		4.0	1.7		4.0
Goodwill		79.8		99.7	79.8		99.7
Corporate & Other
Segment Reporting Information
Revenues	[4]	45.0		45.7	139.7		148.6
Cost of sales	[4]	6.8		21.6	191.0		90.1
Segment profit:
Operating income (loss)	[4]	21.9		5.6	(106.1)		(1.6)
Loss from equity investees	[4]	0.0		0.0	0.0		0.0
Interest expense	[4]	(0.6)		(0.7)	(2.0)		(1.9)
(Loss) income before income taxes	[4]	21.3		4.9	(108.1)		(3.5)
Noncontrolling interests’ net income (loss)	[4]	10.8		(2.0)	(35.5)		(2.0)
Depreciation and amortization	[4]	1.6		1.7	4.8		4.8
Capital expenditures	[4]	2.1		2.5	6.0		6.8
Total assets	[4]	340.3		440.7	340.3		440.7
Short-term borrowings	[4]	0.0		0.0	0.0		0.0
Goodwill	[4]	6.3		7.0	6.3		7.0
Gains (losses) on unsettled commodity derivative instruments, net		$ 18.1		$ 4.2	$ (109.4)		$ (1.8)

[1] Represents the elimination of intersegment transactions principally among Midstream & Marketing, Gas Utility and AmeriGas Propane.

[2] The following table provides a reconciliation of Partnership Adjusted EBITDA to AmeriGas Propane operating income: Three Months EndedJune 30, Nine Months Ended June 30, 2015 2014 2015 2014Partnership Adjusted EBITDA $48.9 $55.1 $579.5 $616.5Depreciation and amortization (48.0) (47.8) (145.5) (149.3)Noncontrolling interests (i) (0.1) (0.1) 3.4 4.5Operating income $0.8 $7.2 $437.4 $471.7(i)Principally represents the General Partner’s 1.01% interest in AmeriGas OLP.

[3] Antargaz interest expense includes pre-tax loss of $10.3 associated with an early extinguishment of debt (see Note 8).

[4] Corporate & Other results principally comprise (1) Electric Utility, (2) Enterprises’ heating, ventilation, air-conditioning, refrigeration and electrical contracting businesses (“HVAC”), (3) net expenses of UGI’s captive general liability insurance company, and (4) UGI Corporation’s unallocated corporate and general expenses and interest income. In addition, Corporate & Other results also include net gains and (losses) on commodity derivative instruments not associated with current-period transactions totaling $18.1 and $4.2 during the three months ended June 30, 2015 and 2014, respectively, and $(109.4) and $(1.8) during the nine months ended June 30, 2015 and 2014, respectively. Corporate & Other assets principally comprise cash, short-term investments, the assets of Electric Utility and HVAC. Through March 2014, Corporate and Other also had an intercompany loan. The intercompany loan interest is removed in the segment presentation.