Employee Retirement Plans (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2014 U.S Pension Plans	Sep. 30, 2013 U.S Pension Plans	Sep. 30, 2012 U.S Pension Plans	Sep. 30, 2014 Supplemental Employee Retirement Plans	Sep. 30, 2013 Supplemental Employee Retirement Plans	Sep. 30, 2013 Portion Used to Fund Company Established Trusts Supplemental Employee Retirement Plans	Sep. 30, 2015 Forecast	Sep. 30, 2014 Other Assets Supplemental Employee Retirement Plans	Sep. 30, 2013 Other Assets Supplemental Employee Retirement Plans	Sep. 30, 2014 Supplemental defined contribution executive retirement plans [Member] Other Assets	Sep. 30, 2013 Supplemental defined contribution executive retirement plans [Member] Other Assets
Defined Benefit Plan Disclosure
Amortization of net actuarial losses										$ 10.3
Amortization of prior service credits										0.2
ABO for the Pension Plans				499.1	451.3
Contribution made to Pension Plan				19.2	22.4	31.2
Projected benefit obligations of unfunded and non qualified supplemental executive retirement plans	38.4	33.9
Net cost to sponsor unfunded and non-qualified supplemental executive retirement plans	2.6	3.0	3.0
Amounts recorded in UGI's stockholders include pre-tax losses representing unrecognized actuarial losses	(10.2)	(9.4)
Amount of expected amortization of pre-tax actuarial losses into retiree benefit cost										0.9
Pension and Other Postretirement Benefit Contributions							0	0	0
Pension and Other Postretirement Benefit Contributions, Fair Value				442.4	398.2						26.6	23.7	3.4	3.4
Percentage of aggregate employer securities holdings to not to exceed fair value assets	10.00%
Percentage of common stock represented pension plan assets	9.60%	8.20%
Costs of benefits under savings plans	$ 14.7	$ 14.0	$ 13.7