Partnership Distributions and Common Unit Offering (Details) (USD $)	12 Months Ended			1 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2010	Mar. 31, 2012 AmeriGas Partners [Member]	Mar. 31, 2012 Senior Notes [Member] 6.50% Pursuant o Tender Offer [Member] AmeriGas Partners [Member]
Distributions Made to Member or Limited Partner [Line Items]
Policy for distribution to partner	45 days after the end of each fiscal quarter in a total amount equal to its Available Cash for such quarter
Approximate distributions day range to partners (in days)	45 days
Pre-Incentive distribution of the available cash to Limited Partners	98.00%
Pre-Incentive distribution of available cash to General Partners	2.00%
General Partner Interest in AmeriGas partners	1.00%
General Partner Interest in AmeriGas OLP	1.01%
Minimum quarterly distribution	$ 0.55
First target distribution	$ 0.055
Incentive distribution policy	When Available Cash exceeds $0.605 per Common Unit in any quarter, the General Partner will receive a greater percentage of the total Partnership distribution (the “incentive distribution”) but only with respect to the amount by which the distribution per Common Unit to limited partners exceeds $0.605
Minimum available cash for per common unit	$ 0.605
General Partners distribution based on ownership interest	$ 19,700,000	$ 9,000,000	$ 6,900,000
Incentive distributions received by the General partner	13,000,000	5,000,000	3,000,000
Units sold in public offering				7,000,000
Underwriteen public offering price per unit				41.25
Issuances of AmeriGas Partners Common Units	276,600,000	0	0	276,600,000
General partners' contributed capital				2,800,000
Aggregate principal amount					$ 200,000,000
Percentage senior notes due (as a percent)					6.50%