Employee Retirement Plans (Details Textual) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2010
Defined Benefit Plan Disclosure [Line Items]
Amortization of net actuarial losses	$ (15.4)
Amortization of prior service credits	(0.1)
Projected benefit obligations of unfunded and non qualified supplemental executive retirement plans	29.5	25.6
Net cost to sponsor unfunded and non-qualified supplemental executive retirement plans	3.0	3.0	2.6
Amounts recorded in UGI's stockholders include pre-tax losses representing unrecognized actuarial losses	(11.0)	(7.6)
Amount of expected amortization of pre-tax actuarial losses into retiree benefit cost	0.7
Percentage of Aggregate Employer Securities Holdings to Not to Exceed Fair Value Assets	10.00%
Percentage of UGI Common Stock represented Pension Plan Assets	7.50%	7.60%
Cost of benefits under the 401(k) savings plan	13.7	10.4	9.8
Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Assumed domestic health care cost range	7.00%
Minimum [Member]
Defined Benefit Plan Disclosure [Line Items]
Assumed domestic health care cost range	5.00%
U.S Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
ABO for the Pension Plans	496.4	415.0
Contribution made to Pension Plan	31.2	18.7	3.4
Expected contribution to pensions plans in next twelve months	$ 16