Selected Quarterly Financial Data - Equity Statement (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	$ 781,453	$ 755,482	$ 781,492	$ 740,814
Exchange of Class B Common Stock for Class A Common Stock	0		0	0
Effect of exchange on deferred tax asset, net of liability under tax receivable agreements	454		454	896
Class A Common Stock dividend		(3,588)	(4,244)	(7,107)
Distributions to non-controlling unitholders		(2,179)	(1,532)	(4,358)
Other distributions and advance payments to non-controlling interest unitholders	(1)	(325)	(805)	(547)
Share repurchases				(17,098)
Stock based compensation expense	4,283	3,571	8,407	6,451
RSU Vesting	(403)	(1,039)	(403)	(1,039)
Restricted stock and RSU forfeitures	6	1	6	2
Net (loss) income	(65,835)	40,523	(63,418)	74,432
Ending balance	$ 719,957	$ 792,446	719,957	$ 792,446
Distributions to noncontrolling unitholders (in dollars per share)	$ 0.05	$ 0.10		$ 0.05
Common stock dividend (in dollars per share)	$ 0.05	$ 0.10		$ 0.05
Additional Paid in Capital
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	$ 413,664	$ 314,967	410,596	$ 312,659
Exchange of Class B Common Stock for Class A Common Stock	18,201		18,201	11,413
Effect of exchange on deferred tax asset, net of liability under tax receivable agreements	454		454	896
Other distributions and advance payments to non-controlling interest unitholders	(1)		(1)
Share repurchases				(13,017)
Stock based compensation expense	3,171	3,571	6,172	6,451
RSU Vesting	405	(439)	472	(303)
Restricted stock and RSU forfeitures	(9)	0	(9)	0
Ending balance	435,885	318,099	435,885	318,099
Retained Earnings
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	140,581	133,877	143,105	119,274
Class A Common Stock dividend		(3,588)	(4,244)	(7,107)
Restricted stock and RSU forfeitures	7	1	7	2
Net (loss) income	(45,771)	22,032	(44,051)	40,153
Ending balance	94,817	152,322	94,817	152,322
Total Stockholders’ Equity
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	555,371	449,967	554,827	433,069
Exchange of Class B Common Stock for Class A Common Stock	18,201		18,201	11,413
Effect of exchange on deferred tax asset, net of liability under tax receivable agreements	454		454	896
Class A Common Stock dividend		(3,588)	(4,244)	(7,107)
Other distributions and advance payments to non-controlling interest unitholders	(1)		(1)
Share repurchases				(13,030)
Stock based compensation expense	3,171	3,571	6,172	6,451
RSU Vesting	409	(436)	476	(300)
Restricted stock and RSU forfeitures	(3)	1	(3)	2
Net (loss) income	(45,771)	22,032	(44,051)	40,153
Ending balance	531,831	471,547	531,831	471,547
Non-controlling Interest
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	226,082	305,515	226,665	307,745
Exchange of Class B Common Stock for Class A Common Stock	(18,201)		(18,201)	(11,413)
Distributions to non-controlling unitholders		(2,179)	(1,532)	(4,358)
Other distributions and advance payments to non-controlling interest unitholders	0	(325)	(804)	(547)
Share repurchases				(4,068)
Stock based compensation expense	1,112		2,235	0
RSU Vesting	(812)	(603)	(879)	(739)
Restricted stock and RSU forfeitures	9	0	9	0
Net (loss) income	(20,064)	18,491	(19,367)	34,279
Ending balance	$ 188,126	$ 320,899	$ 188,126	$ 320,899
Shares of Class A Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance (in shares)			81,885,384
Ending balance (in shares)	84,853,084		84,853,084
Shares of Class A Common Stock | Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance (in shares)	81,920,000	68,744,000	81,885,000	68,360,000
Beginning balance	$ 819	$ 687	$ 819	$ 684
Exchange of Class B Common Stock for Class A Common Stock	$ 26		$ 26	$ 16
Exchanges of Class B Common Stock for Class A Common Stock (shares)	2,558,000		2,558,000	1,637,000
Share repurchase (shares)				(1,303,000)
Share repurchases				$ (13)
RSU Vesting (in shares)	379,000	218,000	414,000	268,000
RSU Vesting	$ 4	$ 3	$ 4	$ 3
Restricted stock and RSU forfeitures (shares)	(4,000)	0	(4,000)	0
Restricted stock and RSU forfeitures	$ (1)	$ 0	$ (1)	$ 0
Ending balance (in shares)	84,853,000	68,962,000	84,853,000	68,962,000
Ending balance	$ 848	$ 690	$ 848	$ 690
Common stock dividend (in dollars per share)			$ 0.05
Shares of Class B Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance (in shares)			30,638,960
Ending balance (in shares)	28,080,525		28,080,525
Shares of Class B Common Stock | Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance (in shares)	30,639,000	43,570,000	30,639,000	45,207,000
Beginning balance	$ 307	$ 436	$ 307	$ 452
Exchange of Class B Common Stock for Class A Common Stock	$ (26)		$ (26)	$ (16)
Exchanges of Class B Common Stock for Class A Common Stock (shares)	(2,558,000)		(2,558,000)	(1,637,000)
Ending balance (in shares)	28,081,000	43,570,000	28,081,000	43,570,000
Ending balance	$ 281	$ 436	$ 281	$ 436