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Acquisitions and dispositions.

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Business acquisition purchase price allocation estimated working capital.

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Cash received from acquired entity under agreement on working capital adjustment.

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The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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Acquisitions and Dispositions (Details Textual) (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended					12 Months Ended										3 Months Ended	12 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009	Oct. 17, 2011	Sep. 25, 2008	Sep. 30, 2008 Central Penn Propane [Member] AmeriGas [Member]	Sep. 30, 2009 CPG Acquisition [Member]	Sep. 30, 2011 AmeriGas [Member]	Sep. 30, 2010 AmeriGas [Member]	Sep. 30, 2009 AmeriGas [Member]	Sep. 30, 2011 International Propane [Member]	Sep. 30, 2010 International Propane [Member]	Sep. 30, 2009 Flaga [Member]	Sep. 30, 2009 UGI Utilities [Member]	Sep. 30, 2008 UGI Utilities [Member] 6.375% Notes, due September 2013 [Member]	Sep. 30, 2010 Atlantic Energy LLC [Member]	Sep. 30, 2010 Atlantic Energy LLC [Member]	Sep. 30, 2010 Atlantic Energy [Member]
Acquisitions And Dispositions (Textual) [Abstract]
Cash consideration to acquire business	$ 52.5	$ 83.0	$ 322.6				$ 267.6	$ 34.0	$ 34.3	$ 17.9	$ 19.0	$ 48.7	$ 18.2
Ownership percentage acquired												46.00%	50.00%
Estimated working capital of acquired entity for consideration														35.4
Proceeds from issuance of Senior notes	1,480.6		118.0												108.0
UGI Utilities Revolving Credit Facility, Borrowings				500.0											75.0
Interest rate stated percentage															6.375%
Cash proceeds from the sale of the assets of CPP						33.6
Business acquisition purchase price allocation estimated working capital, net							35.4
Purchase price of the CPG acquisition, total							2.9
Payment made by PPL to UGI, in cash and interest, in adjustment pursuant to working capital														9.7
Proceeds from sale of investment in Atlantic Energy		66.6																49.0
Pre-tax gain on the sale which amount is included in other income, net																36.5	36.5
Period of deducting goodwill for income tax							15 years
Acquisitions And Dispositions (Additional Textual) [Abstract]
Business purchase consideration cash contributed by UGI					120
Increase in net income attributable to parent due to gain on sale		17.2	10.4													17.2
Increase in earning per share diluted due to gain on sale		$ 0.16	$ 0.10													$ 0.16
Pre tax gain on sale due partnership			$ 39.9