Segment (Details) - USD ($) $ in Thousands	3 Months Ended									12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015		Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015		Dec. 31, 2014
Segment Reporting Information [Line Items]
Revenue, Net	$ 112,526	$ 92,610	$ 94,897	$ 102,010	$ 97,251		$ 88,389	$ 83,479	$ 89,756	$ 402,043	$ 358,875		$ 332,545
Operating Income (Loss)	54,549	38,924	47,111	54,513	50,952		43,617	39,745	43,143	195,097	177,457		153,007
Segment operating income										207,629	190,013		163,831
Unallocated general and administrative expenses										12,532	12,556		10,824
Interest and financing costs, net										(52,112)	(36,892)		(43,775)
Equity in earnings of equity method investments										14,213	4,803		2,987
Gain on sale of assets and other										677	486		82
Income before Income Taxes	42,995	$ 28,464	$ 39,569	$ 46,847	43,236		$ 35,956	$ 31,394	$ 35,268	157,875	145,854		112,301
Capital expenditures										103,823	193,121		198,686
Identifiable assets	1,884,237				1,777,646	[1]				1,884,237	1,777,646	[1]
Affiliated Entity [Member]
Segment Reporting Information [Line Items]
Revenue, Net										300,072	289,258		275,196
Pipelines [Member]
Segment Reporting Information [Line Items]
Revenue, Net										68,927	66,654		57,349
Operating Income (Loss)										204,923	191,451		164,536
Capital expenditures										59,704	67,406		82,184
Identifiable assets	1,369,756				1,391,055					1,369,756	1,391,055
Refining [Member]
Segment Reporting Information [Line Items]
Revenue, Net										33,044	2,963		0
Operating Income (Loss)										2,706	(1,438)		(705)
Capital expenditures										44,119	125,715		$ 116,502
Identifiable assets	342,506				296,080					342,506	296,080
Other Segments [Member]
Segment Reporting Information [Line Items]
Identifiable assets	$ 171,975				$ 90,511					$ 171,975	$ 90,511

[1] (1) Retrospectively adjusted as described in Note 2.