Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Statement [Abstract]
Operating revenues – related party		$ 452,005	$ 362,619	$ 243,624
Costs and expenses:
Cost of revenues (excluding depreciation expense reflected below)	[1]	108,374	96,115	105,973
Depreciation expense		52,475	45,965	45,678
Other operating expenses		577	0	0
General and administrative expenses	[2]	15,549	15,965	14,520
Total costs and expenses		176,975	158,045	166,171
Operating income		275,030	204,574	77,453
Other income, net		753	284	223
Interest and debt expense, net of capitalized interest	[3]	(36,015)	(14,915)	(6,113)
Income before income tax expense		239,768	189,943	71,563
Income tax expense		1,335	1,112	251
Net income		238,433	188,831	71,312
Less: Net loss attributable to Predecessor		0	(15,422)	(60,566)
Net income attributable to partners		238,433	204,253	131,878
Less: General partner’s interest in net income		49,113	23,553	6,069
Limited partners’ interest in net income		$ 189,320	$ 180,700	$ 125,809
Net income per limited partner unit – basic and diluted:
Common units (in dollars per share)		$ 2.77	$ 2.85	$ 2.12
Subordinated units (in dollars per share)		$ 0.00	$ 2.38	$ 2.07
Weighted-average limited partner units outstanding – basic and diluted:
Common units (shares)		68,220	48,817	31,222
Subordinated units (shares)		0	17,463	28,790
Cash distribution declared per unit (in dollars per unit)		$ 1.87	$ 1.4965	$ 1.1975

[1] Includes cost of revenues (excluding depreciation expense) – related party of $67,067 thousand , $61,649 thousand, and $55,649 thousand for the years ended December 31, 2017, 2016, and 2015, respectively.

[2] Includes general and administrative expenses – related party of $12,858 thousand, $12,539 thousand, and $11,695 thousand for the years ended December 31, 2017, 2016, and 2015, respectively.

[3] Includes interest and debt expense – related party of $9,658 thousand, $6,608 thousand, and $3,190 thousand for the years ended December 31, 2017, 2016, and 2015, respectively.