Acquisitions (Details) (USD $)	0 Months Ended												3 Months Ended								10 Months Ended	12 Months Ended				12 Months Ended						0 Months Ended	12 Months Ended	1 Months Ended	12 Months Ended							0 Months Ended	12 Months Ended		12 Months Ended
	Nov. 14, 2012	Aug. 14, 2012	May 14, 2012	Feb. 14, 2012	Nov. 14, 2011	Aug. 12, 2011	May 13, 2011	Feb. 14, 2011	Nov. 12, 2010	Aug. 13, 2010	May 14, 2010	Feb. 12, 2010	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Mar. 02, 2012	Dec. 31, 2012 Pro-forma	Dec. 31, 2011 Pro-forma	Dec. 31, 2010 Pro-forma	Dec. 31, 2012 Selling, general and administrative expenses	Dec. 31, 2011 Selling, general and administrative expenses	Dec. 31, 2010 Selling, general and administrative expenses	Mar. 02, 2012 AE Holdings	Dec. 31, 2012 AE Holdings	Mar. 31, 2012 Alliance	Dec. 31, 2012 Alliance	Dec. 31, 2011 Alliance	Mar. 02, 2012 Alliance	Mar. 02, 2012 Alliance Gasoline Distribution and Station Operations Segment	Mar. 02, 2012 Alliance Environmental	Dec. 31, 2012 Alliance AE Holdings	Mar. 02, 2012 Alliance AE Holdings	Feb. 02, 2012 Alliance AE Holdings Members of Slifka family	Dec. 31, 2012 Mutual Oil item	Dec. 12, 2012 Mutual Oil	Dec. 31, 2010 Retail Gasoline Stations/Fuel Supply Acquisition	Sep. 30, 2010 Retail Gasoline Stations/Fuel Supply Acquisition
Acquisitions
Percentage of outstanding membership interests acquired from AE Holdings																																									100.00%
Affiliate ownership percentage of seller in acquisition																																										95.00%
Cash consideration paid, before adjustment																																					$ 184,500,000
Adjustment in purchase price due to timing of transaction																																					1,900,000
Period of actual unit ownership considered for purchase price adjustment																																31 days		31 days
Period in quarter considered for actual unit ownership																																91 days		91 days
Cash distribution to common units	15,019,000	14,781,000	13,986,000	110,289,000	11,028,000	11,028,000	11,028,000	11,028,000	8,603,000	8,455,000	8,455,000	6,534,000																					1,000,000
Quarterly cash distributions paid (in dollars per unit)	$ 0.5325	$ 0.5250	$ 0.5000	$ 0.5000	$ 0.5000	$ 0.5000	$ 0.5000	$ 0.5000	$ 0.4950	$ 0.4875	$ 0.4875	$ 0.4875		$ 0.5325	$ 0.5250	$ 0.50						$ 0.50											$ 0.50
Miscellaneous adjustments based on certain cash and non-cash changes in operations of acquiree																																					700,000
Summary of the purchase price
Number of common units issued																																5,850,000		5,850,000	5,850,000
Fair value of common units issued in equity consideration (in dollars per share)																									$ 22.31
Total fair value of common units issued																																					130,513,000
Cash consideration																																					181,898,000							6,900,000		202,313,000
Net assets acquired																																					312,411,000				312,400,000			5,700,000
Assets purchased:
Accounts receivable																																					18,801,000
Inventory																																					11,421,000
Prepaid expenses																																					3,235,000
Property and equipment																																					294,461,000	294,500,000
Intangibles																																					31,135,000									7,400,000
Other non-current assets																																					4,861,000
Total identifiable assets purchased																																					363,914,000
Liabilities assumed:
Accounts payable																																					(36,975,000)
Assumption of environmental liabilities (Note 9)																																							(16,075,000)							(30,000,000)
Trustee taxes payable																																					(9,969,000)
Accrued expenses																																					(2,211,000)
Long-term deferred taxes																																					(11,413,000)
Other non-current liabilities																																					(6,292,000)
Total liabilities assumed																																					(82,935,000)
Net identifiable assets acquired																																					280,979,000
Goodwill																																					31,432,000	31,400,000						1,200,000
Net assets acquired																																					312,411,000				312,400,000			5,700,000
Assets retirement obligations included in other long-term liabilities																																								1,700,000
Depreciation expense																													1,800,000	1,200,000	900,000				10,600,000
Intangible assets acquired
Amortization period																						10 years
Amortization expense																																			2,600,000
Estimated remaining amortization expense
2013													7,106,000								7,106,000	7,106,000													3,114,000
2014													7,075,000								7,075,000	7,075,000													3,114,000
2015													6,575,000								6,575,000	6,575,000													3,114,000
2016													5,391,000								5,391,000	5,391,000													3,114,000
2017													5,047,000								5,047,000	5,047,000													3,114,000
Thereafter													29,628,000								29,628,000	29,628,000													12,970,000
Total													60,822,000				36,710,000				60,822,000	60,822,000	36,710,000												28,540,000
Acquisition related costs
Acquisition related costs accrued																																		5,200,000	4,000,000	1,100,000									800,000
Acquisition costs accrued and unpaid																																			100,000
Supplemental Pro-Forma Information
Sales																										17,860,221,000	16,423,411,000	8,948,933,000
Net income																										40,999,000	40,189,000	33,271,000
Net income per limited partner unit, basic (in dollars per unit)													$ 0.81	$ 0.24	$ 0.67	$ (0.06)	$ 0.46	$ 0.08	$ (0.04)	$ 0.40		$ 1.73	$ 0.88	$ 1.61		$ 1.46	$ 1.45	$ 1.46
Net income per limited partner unit, diluted (in dollars per unit)													$ 0.81	$ 0.24	$ 0.66	$ (0.06)	$ 0.45	$ 0.08	$ (0.04)	$ 0.39		$ 1.71	$ 0.87	$ 1.59		$ 1.45	$ 1.44	$ 1.44
Alliance receivable
Receivable amount																																					4,700,000
Receivable fair value																																					0
Actual results since acquisition date
Amount of revenues of acquiree																					1,800,000,000
Amount of earnings of acquiree																					$ 26,400,000
Number of gasoline stations acquired																																											6