Consolidated Statements of Partner's Capital (USD $) In Thousands, except Share data	3 Months Ended				12 Months Ended
	Sep. 30, 2011	Dec. 31, 2010	Sep. 30, 2010	Dec. 31, 2009	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
Beginning Balance		$ 392,886		$ 376,325	$ 392,886	$ 376,325	$ 258,098
Net income	(45,305)	75,781	(41,126)	84,954	140,924	167,494	227,610
Net gains (losses) on derivative instruments					22,275	37,568	(138,317)
Reclassification of net (gains) losses on derivative instruments					(32,243)	(25,629)	195,851
Distributions					(174,093)	(163,850)	(167,682)
Unit-based compensation expense					1,497	1,312	1,093
General Partner contribution to AmeriGas Propane, L.P.					787
Common Units issued in connection with employee and director plans, net of tax withheld					(554)	(334)	(328)
Ending Balance	351,479		392,886		351,479	392,886	376,325
Noncontrolling Interests
Beginning Balance		12,038		11,866	12,038	11,866	10,723
Net income					2,401	2,281	2,967
Net gains (losses) on derivative instruments					225	379	(1,531)
Reclassification of net (gains) losses on derivative instruments					(356)	(264)	2,107
Distributions					(2,272)	(2,224)	(2,400)
General Partner contribution to AmeriGas Propane, L.P.					787
Ending Balance	12,823		12,038		12,823	12,038	11,866
Total AmeriGas Partners, L.P. partners' capital
Beginning Balance		380,848		364,459	380,848	364,459	247,375
Net income					138,523	165,213	224,643
Net gains (losses) on derivative instruments					22,050	37,189	(136,786)
Reclassification of net (gains) losses on derivative instruments					(31,887)	(25,365)	193,744
Distributions					(171,821)	(161,626)	(165,282)
Unit-based compensation expense					1,497	1,312	1,093
Common Units issued in connection with employee and director plans, net of tax withheld					(554)	(334)	(328)
Ending Balance	338,656		380,848		338,656	380,848	364,459
Common
Beginning Balance		372,220		367,708	372,220	367,708	308,186
Beginning Balance, Units		57,088,509		57,046,388	57,088,509	57,046,388	57,009,951
Net income					132,101	160,522	217,906
Distributions					(165,066)	(156,971)	(159,139)
Unit-based compensation expense					1,497	1,312	1,093
Common Units issued in connection with employee and director plans, net of tax withheld					(572)	(351)	(338)
Common Units issued in connection with incentive compensation plans, net of tax withheld, Units					35,787	42,121	36,437
Ending Balance	340,180		372,220		340,180	372,220	367,708
Ending Balance, Units	57,124,296		57,088,509		57,124,296	57,088,509	57,046,388
General partner
Beginning Balance		3,751		3,698	3,751	3,698	3,094
Net income					6,422	4,691	6,737
Distributions					(6,755)	(4,655)	(6,143)
Common Units issued in connection with employee and director plans, net of tax withheld					18	17	10
Ending Balance	3,436		3,751		3,436	3,751	3,698
Accumulated other comprehensive income (loss)
Beginning Balance		4,877		(6,947)	4,877	(6,947)	(63,905)
Net gains (losses) on derivative instruments					22,050	37,189	(136,786)
Reclassification of net (gains) losses on derivative instruments					(31,887)	(25,365)	193,744
Ending Balance	$ (4,960)		$ 4,877		$ (4,960)	$ 4,877	$ (6,947)