Condensed Consolidated Statements of Equity - USD ($) shares in Thousands, $ in Thousands	Class A common stock Common Stock [Member]	Class B common stock Common Stock [Member]	(Accumulated Deficit)	Accumulated Other Comprehensive (Loss) Income	Additional Paid-In Capital	Non-controlling Interest	Total
Beginning Balance at Dec. 31, 2017	$ 13	$ 8	$ (3,493)	$ (687)	$ 70,873	$ 38,130	$ 104,844
Beginning Balance (in shares) at Dec. 31, 2017	13,223	8,268
Increase (Decrease) in Stockholders' Equity
Issuance of equity for business combination		$ 4		112	36,280	53,635	90,031
Issuance of equity for business combination (in shares)		4,200
Exchange of LLC Interests held by LLC Owners	$ 6	$ (6)		(254)	43,920	(43,666)
Exchange of LLC Interests held by LLC Owners (in shares)	5,874	5,874
Net increase in deferred tax asset from LLC Interest transactions					35,621		35,621
Accrued tax distributions						(844)	(844)
Other comprehensive loss				(220)		(80)	(300)
Stock based compensation expense					1,757	921	2,678
Exercise of Options to purchase Common Stock					1,429		1,429
Exercise of Options to purchase Common Stock (in shares)	76
Net (loss) income			2,692			2,651	5,343
Ending Balance at Sep. 30, 2018	$ 19	$ 7	(976)	(1,049)	189,880	50,637	238,518
Ending Balance (in shares) at Sep. 30, 2018	19,172	6,594
Beginning Balance at Jun. 30, 2018	$ 16	$ 9	(3,197)	(913)	146,054	67,039	209,008
Beginning Balance (in shares) at Jun. 30, 2018	16,648	9,043
Increase (Decrease) in Stockholders' Equity
Exchange of LLC Interests held by LLC Owners	$ 3	$ (3)		(136)	18,403	(18,267)
Exchange of LLC Interests held by LLC Owners (in shares)	2,448	(2,448)
Net increase in deferred tax asset from LLC Interest transactions					23,116		23,116
Accrued tax distributions						(151)	(151)
Other comprehensive loss						(11)	(11)
Stock based compensation expense					878	346	1,224
Exercise of Options to purchase Common Stock					1,429		1,429
Exercise of Options to purchase Common Stock (in shares)	76
Net (loss) income			2,221			1,681	3,902
Ending Balance at Sep. 30, 2018	$ 19	$ 7	(976)	(1,049)	189,880	50,637	238,518
Ending Balance (in shares) at Sep. 30, 2018	19,172	6,594
Increase (Decrease) in Stockholders' Equity
ASC 606 adoption, net of tax			(175)			(110)	(285)
Beginning Balance at Dec. 31, 2018	$ 22	$ 7	(4,450)	(1,316)	262,219	64,496	320,977
Beginning Balance (in shares) at Dec. 31, 2018	21,620	6,547
Increase (Decrease) in Stockholders' Equity
Exchange of LLC Interests held by LLC Owners	$ 1	$ (2)		(96)	15,759	(15,663)
Exchange of LLC Interests held by LLC Owners (in shares)	1,590	(1,590)
Net increase in deferred tax asset from LLC Interest transactions					9,517		9,517
Accrued tax distributions						(103)	(103)
Other comprehensive loss				(249)		(53)	(302)
Stock based compensation expense					3,727	1,020	4,747
Exercise of Options to purchase Common Stock					1,588		$ 1,588
Exercise of Options to purchase Common Stock (in shares)	81						81
Issuance of stock for vesting of RSU's (in shares)	11
Net (loss) income			(464)			(88)	$ (552)
Ending Balance at Sep. 30, 2019	$ 23	$ 5	(4,914)	(1,661)	$ 292,810	49,610	335,873
Ending Balance (in shares) at Sep. 30, 2019	23,302	4,957			292,810
Beginning Balance at Jun. 30, 2019	$ 22	$ 7	976	(1,327)	$ 282,343	56,157	338,178
Beginning Balance (in shares) at Jun. 30, 2019	22,750	5,462
Increase (Decrease) in Stockholders' Equity
Exchange of LLC Interests held by LLC Owners	$ 1	$ (1)		(100)	4,951	(4,851)
Exchange of LLC Interests held by LLC Owners (in shares)	505	(505)
Net increase in deferred tax asset from LLC Interest transactions					3,424		3,424
Accrued tax distributions						949	949
Other comprehensive loss				(234)		(39)	(273)
Stock based compensation expense					1,302	299	1,601
Exercise of Options to purchase Common Stock					790		790
Exercise of Options to purchase Common Stock (in shares)	43
Issuance of stock for vesting of RSU's (in shares)	3
Net (loss) income			(5,890)			(2,906)	(8,796)
Ending Balance at Sep. 30, 2019	$ 23	$ 5	$ (4,914)	$ (1,661)	$ 292,810	$ 49,610	$ 335,873
Ending Balance (in shares) at Sep. 30, 2019	23,302	4,957			292,810