Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Income Statement [Abstract]
Operating revenues	$ 544,092	$ 487,950	$ 1,542,167	$ 1,368,334
Costs of sales	502,517	448,812	1,421,524	1,251,491
Gross profit	41,575	39,138	120,643	116,843
Income from CST Fuel Supply equity interests	3,752	4,022	11,185	12,318
Operating expenses:
Operating expenses	15,371	14,224	46,853	45,754
General and administrative expenses	5,994	6,142	23,731	18,068
Depreciation, amortization and accretion expense	14,049	13,432	42,675	40,594
Total operating expenses	35,414	33,798	113,259	104,416
Gain on sales of assets, net	2,371	631	2,013	525
Operating income	12,284	9,993	20,582	25,270
Other income (expense), net	121	(59)	366	375
Interest expense	(7,102)	(5,634)	(20,599)	(16,403)
Income before income taxes	5,303	4,300	349	9,242
Income tax expense (benefit)	966	1,308	(1,686)	851
Net income	4,337	2,992	2,035	8,391
Less: net income (loss) attributable to noncontrolling interests	4	3	(1)	9
Net income attributable to limited partners	4,333	2,989	2,036	8,382
IDR distributions	(1,115)	(877)	(3,162)	(2,456)
Net income (loss) available to limited partners	$ 3,218	$ 2,112	$ (1,126)	$ 5,926
Net income (loss) per limited partner unit:
Basic earnings per common unit	$ 0.09	$ 0.06	$ (0.03)	$ 0.18
Diluted earnings per common unit	$ 0.09	$ 0.06	$ (0.03)	0.18
Basic and diluted earnings per subordinated unit				$ 0.18
Weighted-average limited partner units:
Basic common units	33,931,056	33,366,380	33,773,964	31,714,462
Diluted common units	33,937,702	33,391,096	33,773,964	31,766,802
Basic and diluted subordinated units				1,537,956
Total diluted common and subordinated units	33,937,702	33,391,096	33,773,964	33,304,758
Distribution paid per common and subordinated unit	$ 0.6225	$ 0.6025	$ 1.8525	$ 1.7925
Distribution declared (with respect to each respective period) per common and subordinated unit	$ 0.6275	$ 0.6075	$ 1.8675	$ 1.8075
Supplemental information:
(a) Includes excise taxes of:	$ 19,704	$ 19,698	$ 58,351	$ 59,902
(a) Includes revenues from fuel sales to related parties of:	101,190	99,891	281,611	280,330
(a) Includes rental income of:	21,644	19,752	65,090	59,634
(b) Includes rental expense of:	$ 4,876	$ 5,103	$ 14,593	$ 14,870