Common Stock And Equity Based Compensation (Details Textual) (USD $) In Millions, except Share data, unless otherwise specified	1 Months Ended	12 Months Ended						3 Months Ended	12 Months Ended														0 Months Ended	1 Months Ended	12 Months Ended			1 Months Ended
	Mar. 31, 2012	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2012 Employee Stock Option [Member]	Sep. 30, 2012 Equity Instruments Other Than Option [Member]	Sep. 30, 2012 Omnibus Equity Compensation Plan [Member]	Dec. 31, 2011 2010 Propane Plan [Member]	Sep. 30, 2012 2010 Propane Plan [Member]	Sep. 30, 2011 2010 Propane Plan [Member]	Sep. 30, 2010 2010 Propane Plan [Member]	Sep. 30, 2012 UGI Stock Units [Member]		Sep. 30, 2011 UGI Stock Units [Member]	Sep. 30, 2010 UGI Stock Units [Member]	Sep. 30, 2012 UGI Performance Units [Member]	Sep. 30, 2011 UGI Performance Units [Member]	Sep. 30, 2010 UGI Performance Units [Member]	Sep. 30, 2012 AmeriGas Performance Unit [Member]	Sep. 30, 2011 AmeriGas Performance Unit [Member]	Sep. 30, 2010 AmeriGas Performance Unit [Member]	Jun. 30, 2010 AmeriGas Performance Unit [Member]	Jan. 12, 2012 Heritage Propane [Member]	Mar. 31, 2012 Noncontrolling Interest [Member]	Sep. 30, 2012 Noncontrolling Interest [Member]	Sep. 30, 2011 Noncontrolling Interest [Member]	Sep. 30, 2010 Noncontrolling Interest [Member]	Mar. 31, 2012 AmeriGas Partners [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common units issued by AmeriGas Partners (in units)																							29,567,362
Units sold in public offering																												7,000,000
Increase in Stockholders' Equity, Net of Deferred Income Taxes	$ 196.3
Adjustments to reflect change in ownership of Amerigas Partners, net of tax																								(321.4)	(321.4)	0	0
Pre-tax equity-based compensation expense		14.5	15.6	13.2
After tax equity-based compensation expense		8.7	10.3	8.7
Options can be exercised																			no later than ten years from the grant date
Granted Under Plan Term (in years)		10 years
Shares of UGI Common Stock granted as awards					15,000,000	3,200,000																2,800,000
Cash received from stock option exercises		16.8	22.9	23.1
Associated tax benefits		2.3	3.8	4.3
Unrecognized compensation cost associated with unvested Amerigas unit awards		4.2										5.2							3.0
Weighted-average fair value of stock option granted under stock plans		$ 4.31	$ 5.40	$ 4.49					$ 43.22	$ 53.19	$ 41.39					$ 27.25	$ 35.19	$ 22.51
Target award paid to employee																grantees may receive 0% to 200% of the target award granted. If UGI’s TSR ranks below the 40th percentile compared to the UGI comparator group, the employee will not be paid. At the 40th percentile, the employee will be paid an award equal to 50% of the target award; at the 50th percentile, 100%; and at the 100th percentile, 200%
Minimum percentage amount of guarantee on target award granted																0.00%
Maximum percentage amount of guarantee on target award granted																200.00%
Percentage of target award paid at 40th percentile																50.00%
Percentage of target award paid at 50th percentile																100.00%
Percentage of target award paid at 100th percentile																200.00%
Expected term of Performance Unit awards																3 years			3 years
Shares granted under UGI Stock Unit awards		approximately 70% in shares
Number of UGI Units, Granted		239,845	285,470	231,710					248,818	49,287	57,750	42,445	[1]	61,945	27,060	197,400			55,150
Weighted average grant date fair value unit awards		$ 27.68	$ 34.78	$ 22.69								$ 29.69	[1]			$ 27.25			$ 48.28
Unrecognized compensation cost associated with common unit												885,338							263,967
Weighted-average period for unvested Amerigas unit awards		2 years										1 year 10 months 24 days							2 years 0 months
Performance units ultimately paid								3 years
Number of common units subject to original awards granted						1,436,672	1,436,672		2,517,419
Fair value of AmeriGas units vested												3.6		6.8	5.0				5.1	2.0	2.0
Liabilities associated with share based compensation												$ 5.0		$ 6.0					$ 1.1	$ 1.2

[1] Generally, shares granted under UGI Stock Unit awards are paid approximately 70% in shares. UGI Stock Unit awards granted in Fiscal 2011 and Fiscal 2010 were 61,945 and 27,060, respectively.