Segment Information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended														12 Months Ended
	Sep. 30, 2012		Jun. 30, 2012	Mar. 31, 2012		Dec. 31, 2011		Sep. 30, 2011		Jun. 30, 2011	Mar. 31, 2011		Dec. 31, 2010		Sep. 30, 2012		Sep. 30, 2011		Sep. 30, 2010
Segment information
Revenues	$ 1,125.7	[1]	$ 1,277.2	$ 2,427.5	[2]	$ 1,688.8	[3]	$ 1,039.3	[1]	$ 1,105.4	$ 2,181.0	[4]	$ 1,765.6	[5]	$ 6,519.2		$ 6,091.3		$ 5,591.4
Cost of sales															4,111.2		4,010.9		3,584.0
Operating income (loss)	(28.6)	[1]	(19.2)	380.8	[2]	188.3	[3]	(10.5)	[1]	17.2	357.0	[4]	252.3	[5]	521.3		616.0		659.2
Loss from equity investees	(0.1)	[1]	(0.1)	0	[2]	(0.1)	[3]	(0.1)	[1]	(0.2)	(0.4)	[4]	(0.2)	[5]	(0.3)		(0.9)		(2.1)
Loss on extinguishments of debt	0	[1]	0.1	(13.4)	[2]	0	[3]	(19.3)	[1]	0	(18.8)	[4]	0	[5]	(13.3)		(38.1)
Interest expense															(221.5)		(138.0)		(133.8)
Income (loss) before income taxes															286.2		439.0		523.3
Net income (loss) attributable to UGI	(14.7)	[1]	(6.3)	133.4	[2]	87.0	[3]	(22.4)	[1]	(7.2)	149.4	[4]	113.1	[5]	199.4		232.9		261.0
Depreciation and amortization															316.0		227.9		210.2
Noncontrolling interests' net (loss) income															(12.8)		75.3		94.7
Total assets	9,709.7							6,663.3							9,709.7		6,663.3		6,374.0
Bank loans	165.1							138.7							165.1		138.7		200.4
Capital expenditures															343.2		355.6		352.9
Investments in equity investees	0.3							0.3							0.3		0.3		0.4
Goodwill	2,818.3							1,562.2							2,818.3		1,562.2		1,562.7
Eliminations [Member]
Segment information
Revenues															(178.8)	[6]	(233.0)	[6]	(203.9)	[6]
Cost of sales															(174.0)	[6]	(228.6)	[6]	(197.1)	[6]
Operating income (loss)																	0		0
Loss from equity investees
Income (loss) before income taxes																	0		0
Net income (loss) attributable to UGI																	0		0
Noncontrolling interests' net (loss) income
Total assets	(104.1)							(93.3)							(104.1)		(93.3)		(81.1)
Goodwill
AmeriGas Propane [Member]
Segment information
Revenues															2,921.6		2,538.0		2,320.3
Cost of sales															1,719.7		1,605.3		1,395.1
Operating income (loss)															170.3		242.9		235.8
Loss from equity investees
Loss on extinguishments of debt															(13.3)		(38.1)
Interest expense															(142.6)		(63.5)		(65.1)
Income (loss) before income taxes															14.4		141.3		170.7
Net income (loss) attributable to UGI															15.9		39.9		47.3
Depreciation and amortization															169.1		94.7		87.4
Noncontrolling interests' net (loss) income															(13.0)		75.0		91.1
Partnership EBITDA															324.7	[7]	297.1	[7]	321.0	[7]
Total assets	4,539.6							1,800.4							4,539.6		1,800.4		1,690.6
Bank loans	49.9							95.5							49.9		95.5		91.0
Capital expenditures															103.1		77.2		83.2
Goodwill	1,919.2							696.3							1,919.2		696.3		683.1
Gas Utility [Member]
Segment information
Revenues															785.4		1,026.4		1,047.5
Cost of sales															402.5		610.6		653.4
Operating income (loss)															172.2		199.6		175.3
Loss from equity investees
Interest expense															(40.1)		(40.4)		(40.5)
Income (loss) before income taxes															132.1		159.2		134.8
Net income (loss) attributable to UGI															80.5		99.3		83.1
Depreciation and amortization															49.0		48.4		49.5
Noncontrolling interests' net (loss) income																			0
Total assets	2,070.4							2,028.7							2,070.4		2,028.7		1,996.3
Bank loans	9.2														9.2				17.0
Capital expenditures															109.0		91.3		73.5
Goodwill	182.1							182.1							182.1		182.1		180.1
Energy Services [Member]
Segment information
Revenues															816.4		1,023.8		1,105.3
Cost of sales															703.8		902.2		998.0
Operating income (loss)															68.9		84.2		110.8
Loss from equity investees
Interest expense															(4.8)		(2.0)		0.1
Income (loss) before income taxes															64.1		82.2		110.7
Net income (loss) attributable to UGI															37.6		48.4		61.2
Depreciation and amortization															3.7		2.4		3.3
Noncontrolling interests' net (loss) income																			3.3
Total assets	368.5							338.2							368.5		338.2		245.8
Bank loans	85.0							24.3							85.0		24.3
Capital expenditures															36.0		63.1		48.3
Goodwill	2.8							2.8							2.8		2.8		2.8
Electric Generation [Member]
Segment information
Revenues															43.0		49.1		58.5
Cost of sales															27.1		31.1		30.6
Operating income (loss)															(6.5)		(1.3)		9.2
Loss from equity investees															0
Interest expense															0		0.7		0.1
Income (loss) before income taxes															(6.5)		(2.0)		9.1
Net income (loss) attributable to UGI															(1.2)		4.1		7.0
Depreciation and amortization															9.0		5.6		4.4
Noncontrolling interests' net (loss) income																			0
Total assets	258.2							242.5							258.2		242.5		205.0
Bank loans	0							0							0		0
Capital expenditures															24.4		49.7		68.1
Goodwill	0							0							0		0		0
Antargaz [Member]
Segment information
Revenues															1,121.3		1,050.6		887.1
Cost of sales															685.5		649.8		465.9
Operating income (loss)															88.2		89.2		115.1
Loss from equity investees															(0.3)		(0.9)		(2.0)
Interest expense															(26.3)		(25.5)		(22.4)
Income (loss) before income taxes															61.6		62.8		90.7
Net income (loss) attributable to UGI															51.3		44.2		60.0
Depreciation and amortization															57.1		52.1		48.9
Noncontrolling interests' net (loss) income															0.2		0.3		0.3
Total assets	1,686.5							1,636.6							1,686.5		1,636.6		1,678.3
Bank loans																			68.2
Capital expenditures															47.3		48.9		51.4
Goodwill	612.0							591.8							612.0		591.8		602.7
Flaga & Other [Member]
Segment information
Revenues															824.7		438.1		172.4
Cost of sales															640.3		321.0		116.2
Operating income (loss)															23.6		(3.1)		1.9
Loss from equity investees																			(0.1)
Interest expense															(4.6)		(2.7)		(3.0)
Income (loss) before income taxes															19.0		(5.8)		(1.2)
Net income (loss) attributable to UGI															13.8		(3.2)		(1.2)
Depreciation and amortization															22.1		18.5		11.5
Noncontrolling interests' net (loss) income															0
Total assets	531.8							428.8							531.8		428.8		320.2
Bank loans	21.0							18.9							21.0		18.9		24.2
Capital expenditures															16.9		16.5		7.6
Investments in equity investees	0.3							0.3							0.3		0.3		0.4
Goodwill	95.2							82.2							95.2		82.2		87.0
Corporate & Other [Member]
Segment information
Revenues															185.6	[8]	198.3	[8]	204.2	[8]
Cost of sales															106.3	[8]	119.5	[8]	121.9	[8]
Operating income (loss)															4.6	[8]	4.5	[8]	11.1	[8]
Loss from equity investees																[8]
Interest expense															(3.1)	[8]	(3.2)	[8]	(2.6)	[8]
Income (loss) before income taxes															1.5	[8]	1.3	[8]	8.5	[8]
Net income (loss) attributable to UGI															1.5	[8]	0.2	[8]	3.6	[8]
Depreciation and amortization															6.0	[8]	6.2	[8]	5.2	[8]
Noncontrolling interests' net (loss) income																				[8]
Total assets	358.8	[8]						281.4	[8]						358.8	[8]	281.4	[8]	318.9	[8]
Bank loans									[8]									[8]		[8]
Capital expenditures															6.5	[8]	8.9	[8]	20.8	[8]
Investments in equity investees									[8]									[8]
Goodwill	$ 7.0	[8]						$ 7.0	[8]						$ 7.0	[8]	$ 7.0	[8]	$ 7.0	[8]

[1] Includes loss on extinguishment of Partnership long-term debt which increased net loss attributable to UGI Corporation by $5.2 or $0.05 per diluted share (see Note 5).

[2] Includes loss on extinguishment of Partnership long-term debt which decreased net income attributable to UGI Corporation by $2.2 or $0.02 per diluted share (see Note 5).

[3] Includes adjustment to foreign tax credit valuation allowance which increased net income by $5.5 or $0.05 per diluted share.

[4] Includes loss on extinguishment of Partnership long-term debt which decreased net income attributable to UGI Corporation by $5.2 or $0.05 per diluted share (see Note 5).

[5] Includes the reversal of previously recorded nontaxable accrual associated with the Antargaz Competition Authority Matter which increased operating income and net income attributable to UGI Corporation by $9.4 or $0.08 per diluted share (see Note 15).

[6] Principally represents the elimination of intersegment transactions principally among Midstream & Marketing, Gas Utility and AmeriGas Propane.

[7] The following table provides a reconciliation of Partnership EBITDA to AmeriGas Propane operating income:Year ended September 30, 2012 2011 2010 Partnership EBITDA $324.7 $297.1 $321.0 Depreciation and amortization (169.1) (94.7) (87.4) Loss on extinguishments of debt 13.3 38.1 — Noncontrolling interests (i) 1.4 2.4 2.2 Operating income $170.3 $242.9 $235.8 (i)Principally represents the General Partner’s 1.01% interest in AmeriGas OLP.

[8] Corporate & Other results principally comprise Electric Utility, UGI Enterprises’ heating, ventilation, air-conditioning, refrigeration and electrical contracting businesses (“HVAC/R”), net expenses of UGI’s captive general liability insurance company, and UGI Corporation’s unallocated corporate and general expenses and interest income. Corporate & Other assets principally comprise cash, short-term investments, the assets of Electric Utility and HVAC/R, and an intercompany loan. The intercompany loan and associated interest is removed in the segment presentation.