Consolidated Statements of Changes in Equity - USD ($) $ in Thousands	Total	Members' Capital	Common Stock Class A Common Stock	Common Stock Class B Common Stock	Common Stock Class C Common Stock	Common Stock Class D Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Income (Loss)	Retained Earnings	Non- Controlling Interests	PRSU	PRSU Additional Paid-In Capital	RSU	RSU Additional Paid-In Capital
Beginning balance ( in shares) at Dec. 31, 2018			0	0	0	0
Beginning balance at Dec. 31, 2018	$ 4,572,334	$ 4,573,200	$ 0	$ 0	$ 0	$ 0	$ 0	$ (866)	$ 0	$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation expense	4,674	4,674
Adjustment to Class C Shares and Class P(C) shares in mezzanine capital	(2,369)	(2,369)
Capital distributions	(20,000)	(20,000)
Net income	42,352	42,352
Foreign currency translation adjustments	988							988
Ending balance (in shares) at Mar. 31, 2019			0	0	0	0
Ending balance at Mar. 31, 2019	4,597,979	4,597,857	$ 0	$ 0	$ 0	$ 0	0	122	0	0
Beginning balance ( in shares) at Dec. 31, 2018			0	0	0	0
Beginning balance at Dec. 31, 2018	4,572,334	4,573,200	$ 0	$ 0	$ 0	$ 0	0	(866)	0	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	115,746
Ending balance (in shares) at Sep. 30, 2019			46,009,753	96,933,192	10,006,269	69,282,736
Ending balance at Sep. 30, 2019	4,487,236	0	$ 0	$ 1	$ 0	$ 1	2,855,885	(1,854)	19,570	1,613,633
Beginning balance ( in shares) at Mar. 31, 2019			0	0	0	0
Beginning balance at Mar. 31, 2019	4,597,979	4,597,857	$ 0	$ 0	$ 0	$ 0	0	122	0	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Activities related to exchanges of LLC Interests, net of offering costs and cancellations (in shares)			46,000,000	96,933,192	10,006,269	69,282,736
Activities related to exchanges of LLC Interests, net of offering costs and cancellations	(15,854)			$ 1		$ 1	(15,856)
Tax receivable agreement liability and deferred taxes arising from LLC Interest ownership exchanges	(78,232)						(78,232)
Allocation of equity to non-controlling interests	0						(1,607,529)			1,607,529
Distributions to non-controlling interests	(11,909)									(11,909)
Dividends ($0.08 per share)	(11,435)								(11,435)
Stock-based compensation expense											$ 6,763	$ 6,763
Stock-based compensation expense under the Option Plan	20,403						20,403
Capital distributions	(100,000)	(100,000)
Effect of the reorganization transactions	23,275	(4,497,857)					4,521,132
Net income	24,816								12,828	11,988
Foreign currency translation adjustments	(1,006)							(647)		(359)
Ending balance (in shares) at Jun. 30, 2019			46,000,000	96,933,192	10,006,269	69,282,736
Ending balance at Jun. 30, 2019	4,454,800	0	$ 0	$ 1	$ 0	$ 1	2,846,681	(525)	1,393	1,607,249
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Activities related to exchanges of LLC Interests, net of offering costs and cancellations (in shares)			9,753
Activities related to exchanges of LLC Interests, net of offering costs and cancellations	0
Allocation of equity to non-controlling interests	0						73			(73)
Distributions to non-controlling interests	(11,772)									(11,772)
Dividends ($0.08 per share)	(11,435)								(11,435)
Stock-based compensation expense											7,136	7,136
Stock-based compensation expense under the Option Plan	1,995						1,995
Net income	48,578								29,612	18,966
Foreign currency translation adjustments	(2,066)							(1,329)		(737)
Ending balance (in shares) at Sep. 30, 2019			46,009,753	96,933,192	10,006,269	69,282,736
Ending balance at Sep. 30, 2019	4,487,236	$ 0	$ 0	$ 1	$ 0	$ 1	2,855,885	(1,854)	19,570	1,613,633
Ending balance (in shares) at Dec. 31, 2019			66,408,328	96,933,192	8,328,983	50,853,172
Ending balance at Dec. 31, 2019	4,592,745		$ 1	$ 1	$ 0	$ 1	3,329,386	1,366	47,833	1,214,157
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Activities related to exchanges of LLC Interests, net of offering costs and cancellations (in shares)			1,920,941		(939,000)	(981,941)
Activities related to exchanges of LLC Interests, net of offering costs and cancellations	(336)					$ (1)	(335)
Issuance of common stock from equity incentive plans (in shares)			2,341,171
Issuance of common stock from equity incentive plans	35,422						35,422
Tax receivable agreement liability and deferred taxes arising from LLC Interest ownership exchanges	32,736						32,736
Adjustments to non-controlling interests	0						45,436	7		(45,443)
Dividends ($0.08 per share)	(13,400)								(13,400)
Stock-based compensation expense											5,407	5,407	$ 315	$ 315
Stock-based compensation expense under the Option Plan	2,249						2,249
Payroll taxes paid for stock-based compensation exercises	(23,991)						(23,991)
Net income	62,485								43,928	18,557
Foreign currency translation adjustments	(4,784)							(3,552)		(1,232)
Ending balance (in shares) at Mar. 31, 2020			70,670,440	96,933,192	7,389,983	49,871,231
Ending balance at Mar. 31, 2020	4,688,848		$ 1	$ 1	$ 0	$ 0	3,426,625	(2,179)	78,361	1,186,039
Beginning balance ( in shares) at Dec. 31, 2019			66,408,328	96,933,192	8,328,983	50,853,172
Beginning balance at Dec. 31, 2019	4,592,745		$ 1	$ 1	$ 0	$ 1	3,329,386	1,366	47,833	1,214,157
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	151,941
Ending balance (in shares) at Sep. 30, 2020			90,985,582	96,933,192	5,109,991	34,403,255
Ending balance at Sep. 30, 2020	4,879,219		$ 1	$ 1	$ 0	$ 0	3,940,592	100	116,161	822,364
Beginning balance ( in shares) at Mar. 31, 2020			70,670,440	96,933,192	7,389,983	49,871,231
Beginning balance at Mar. 31, 2020	4,688,848		$ 1	$ 1	$ 0	$ 0	3,426,625	(2,179)	78,361	1,186,039
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Activities related to exchanges of LLC Interests, net of offering costs and cancellations (in shares)			17,747,968		(2,279,992)	(15,467,976)
Activities related to exchanges of LLC Interests, net of offering costs and cancellations	(1,406)						(1,406)
Issuance of common stock from equity incentive plans (in shares)			2,223,700
Issuance of common stock from equity incentive plans	27,197						27,197
Tax receivable agreement liability and deferred taxes arising from LLC Interest ownership exchanges	127,846						127,846
Adjustments to non-controlling interests	0						379,623	(249)		(379,374)
Distributions to non-controlling interests	(3,605)									(3,605)
Dividends ($0.08 per share)	(14,483)								(14,483)
Stock-based compensation expense											7,392	7,392	1,675	1,675
Stock-based compensation expense under the Option Plan	1,279						1,279
Payroll taxes paid for stock-based compensation exercises	(47,672)						(47,672)
Net income	42,408								30,496	11,912
Foreign currency translation adjustments	(336)							(265)		(71)
Ending balance (in shares) at Jun. 30, 2020			90,642,108	96,933,192	5,109,991	34,403,255
Ending balance at Jun. 30, 2020	4,829,143		$ 1	$ 1	$ 0	$ 0	3,922,559	(2,693)	94,374	814,901
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Activities related to exchanges of LLC Interests, net of offering costs and cancellations	(766)						(766)
Issuance of common stock from equity incentive plans (in shares)			343,474
Issuance of common stock from equity incentive plans	10,700						10,700
Adjustments to non-controlling interests	0						(1,478)			1,478
Distributions to non-controlling interests	(4,839)									(4,839)
Dividends ($0.08 per share)	(15,025)								(15,025)
Stock-based compensation expense											$ 6,778	$ 6,778	$ 1,684	$ 1,684
Stock-based compensation expense under the Option Plan	1,295						1,295
Payroll taxes paid for stock-based compensation exercises	(180)						(180)
Net income	47,048								36,812	10,236
Foreign currency translation adjustments	3,381							2,793		588
Ending balance (in shares) at Sep. 30, 2020			90,985,582	96,933,192	5,109,991	34,403,255
Ending balance at Sep. 30, 2020	$ 4,879,219		$ 1	$ 1	$ 0	$ 0	$ 3,940,592	$ 100	$ 116,161	$ 822,364