Equity Method Investments - Summarized Financial Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Schedule of Equity Method Investments [Line Items]
Current Assets	$ 43,497		$ 43,497		$ 33,570
Current liabilities	17,975		17,975		35,082
Revenues	117,637	$ 155,342	281,038	$ 307,825
Operating income	47,881	32,256	82,923	61,367
Net Income	44,415	24,885	72,211	44,581
Equity Method Investment, Nonconsolidated Investee or Group of Investees [Member] | Red River
Schedule of Equity Method Investments [Line Items]
Current Assets	11,376		11,376		9,278
Non-current Assets	416,554		416,554		381,778
Current liabilities	17,869		17,869		8,291
Revenues	11,873	14,391	21,969	26,017
Gross Profit	7,175	9,191	13,062	14,466
Operating income	7,000	8,942	12,697	13,652
Net Income	7,025	8,942	12,746	13,652
Equity Method Investment, Nonconsolidated Investee or Group of Investees [Member] | Joint Ventures [Member]
Schedule of Equity Method Investments [Line Items]
Current Assets	20,040		20,040		29,476
Non-current Assets	258,751		258,751		262,300
Current liabilities	2,381		2,381		$ 6,391
Revenues	12,738	10,077	28,185	19,191
Gross Profit	8,198	5,688	18,834	10,584
Operating income	7,724	5,223	17,864	9,624
Net Income	$ 7,729	$ 5,249	$ 17,887	$ 9,666