Condensed Consolidated Statements of Stockholders' Equity (Deficit) - USD ($) $ in Thousands	Additional Paid-in Capital	Retained Earnings (Deficit)	Non-controlling Interest	Common Class A	Common Class B	Common Class C	Total
Balance at Dec. 31, 2018	$ 47,531	$ (3,370)	$ (11,621)	$ 372	$ 5		$ 32,917
Balance (in shares) at Dec. 31, 2018				37,192,000	50,707,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity-based compensation	2,716						2,716
Vesting of restricted stock units (in shares)				1,000
Redemption of LLC common units for Class A common stock	12						12
Redemption of LLC common units for Class A common stock (in shares)				6,000
Distributions to holders of LLC common units			(5,534)				(5,534)
Dividends		(5,699)					(5,699)
Establishment of liabilities under the Tax Receivable Agreement and related changes to deferred tax assets associated with that liability	(8)						(8)
Non-controlling interest adjustment	(1,678)		1,678
Net income loss		(19,395)	(7,412)				(26,807)
Balance at Mar. 31, 2019	48,573	(24,759)	(16,557)	$ 372	$ 5		7,634
Balance (in shares) at Mar. 31, 2019				37,199,000	50,707,000
Balance at Dec. 31, 2018	47,531	(3,370)	(11,621)	$ 372	$ 5		32,917
Balance (in shares) at Dec. 31, 2018				37,192,000	50,707,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income loss							25,816
Balance at Jun. 30, 2019	50,604	(12,453)	(12,916)	$ 373	$ 5		25,613
Balance (in shares) at Jun. 30, 2019				37,273,000	50,707,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Adoption of accounting standard		3,705	6,332				10,037
Balance at Mar. 31, 2019	48,573	(24,759)	(16,557)	$ 372	$ 5		7,634
Balance (in shares) at Mar. 31, 2019				37,199,000	50,707,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity-based compensation	3,863						3,863
Vesting of restricted stock units	143		(144)	$ 1
Vesting of restricted stock units (in shares)				96,000
Repurchases of Class A common stock for withholding taxes on vested RSUs	(273)						(273)
Repurchases of Class A common stock for withholding taxes on vested RSUs (in shares)				(22,000)
Distributions to holders of LLC common units			(32,523)				(32,523)
Dividends		(5,711)					(5,711)
Non-controlling interest adjustment	(1,702)		1,702
Net income loss		18,017	34,606				52,623
Balance at Jun. 30, 2019	50,604	(12,453)	(12,916)	$ 373	$ 5		25,613
Balance (in shares) at Jun. 30, 2019				37,273,000	50,707,000
Balance at Dec. 31, 2019	50,152	(83,134)	(126,634)	$ 375	$ 5		(159,236)
Balance (in shares) at Dec. 31, 2019				37,488,989	50,706,629	1
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity-based compensation	3,312						3,312
Vesting of restricted stock units	82		(82)
Vesting of restricted stock units (in shares)				47,000
Repurchases of Class A common stock for withholding taxes on vested RSUs	(212)						(212)
Repurchases of Class A common stock for withholding taxes on vested RSUs (in shares)				(16,000)
Redemption of LLC common units for Class A common stock	4		49				53
Redemption of LLC common units for Class A common stock (in shares)				20,000
Distributions to holders of LLC common units			(8,410)				(8,410)
Dividends		(5,752)					(5,752)
Establishment of liabilities under the Tax Receivable Agreement and related changes to deferred tax assets associated with that liability	(44)						(44)
Non-controlling interest adjustment	(1,698)		1,698
Net income loss		(8,160)	(5,969)				(14,129)
Balance at Mar. 31, 2020	51,596	(97,046)	(139,348)	$ 375	$ 5		(184,418)
Balance (in shares) at Mar. 31, 2020				37,540,000	50,707,000
Balance at Dec. 31, 2019	50,152	(83,134)	(126,634)	$ 375	$ 5		(159,236)
Balance (in shares) at Dec. 31, 2019				37,488,989	50,706,629	1
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income loss							149,093
Balance at Jun. 30, 2020	52,747	(44,754)	(78,315)	$ 378	$ 5		(69,939)
Balance (in shares) at Jun. 30, 2020				37,773,109	50,706,629	1
Balance at Mar. 31, 2020	51,596	(97,046)	(139,348)	$ 375	$ 5		(184,418)
Balance (in shares) at Mar. 31, 2020				37,540,000	50,707,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity-based compensation	4,182						4,182
Exercise of stock options	159						159
Exercise of stock options (in shares)				7,000
Non-controlling interest adjustment for capital contribution of proceeds from the exercise of stock options	(105)		105
Vesting of restricted stock units	(10)		8	$ 2
Vesting of restricted stock units (in shares)				153,000
Repurchases of Class A common stock for withholding taxes on vested RSUs	(347)						(347)
Repurchases of Class A common stock for withholding taxes on vested RSUs (in shares)				(17,000)
Redemption of LLC common units for Class A common stock	58		245	$ 1			304
Redemption of LLC common units for Class A common stock (in shares)				90,000
Distributions to holders of LLC common units			(47,015)				(47,015)
Dividends		(5,785)					(5,785)
Establishment of liabilities under the Tax Receivable Agreement and related changes to deferred tax assets associated with that liability	(241)						(241)
Non-controlling interest adjustment	(2,545)		2,545
Net income loss		58,077	105,145				163,222
Balance at Jun. 30, 2020	$ 52,747	$ (44,754)	$ (78,315)	$ 378	$ 5		$ (69,939)
Balance (in shares) at Jun. 30, 2020				37,773,109	50,706,629	1