Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Common Stock	Additional Paid-in Capital	Accumulated Deficit Cumulative effect of a change in accounting principle	Accumulated Deficit	Accumulated Other Comprehensive Loss	Non-controlling Interests Cumulative effect of a change in accounting principle	Non-controlling Interests	Cumulative effect of a change in accounting principle	Total
Balance at Dec. 31, 2017	$ 4	$ 230,679		$ (131,967)	$ (898)		$ 1,212		$ 99,030
Balance (in shares) at Dec. 31, 2017	40,995,000
Issuance of common stock under stock incentive plans		9,979							9,979
Issuance of common stock under stock incentive plans (in shares)	1,674,000
Shares withheld for taxes		(10,536)							(10,536)
Stock-based compensation expense		13,057							13,057
Equity component of Convertible Notes, net of offering costs and tax		39,922							39,922
Payment for capped call share options		(23,969)							(23,969)
Non-controlling interest distributions							(614)		(614)
Net (loss) income				(1,220)			1,489		269
Other comprehensive loss					(397)		55		(342)
Balance at Dec. 31, 2018	$ 4	259,132	$ 3,257	(129,930)	(1,295)	$ 69	2,211	$ 3,326	130,122
Balance (in shares) at Dec. 31, 2018	42,669,000
Issuance of common stock under stock incentive plans		470							470
Issuance of common stock under stock incentive plans (in shares)	1,611,000
Repurchases of common stock				(747)					$ (747)
Repurchases of common stock (in shares)	(56,000)								(56,000)
Shares withheld for taxes		(34,420)							$ (34,420)
Stock-based compensation expense		9,456							9,456
Non-controlling interest distributions							(1,003)		(1,003)
Net (loss) income				(10,296)			19		(10,277)
Other comprehensive loss					(131)		11		(120)
Balance at Dec. 31, 2019	$ 4	234,638		(140,973)	(1,426)		1,238		$ 93,481
Balance (in shares) at Dec. 31, 2019	44,224,000								44,224,000
Issuance of common stock under stock incentive plans		708							$ 708
Issuance of common stock under stock incentive plans (in shares)	407,000
Repurchases of common stock (in shares)									0
Shares withheld for taxes		(1,730)							$ (1,730)
Stock-based compensation expense		8,252							8,252
Non-controlling interest distributions							(262)		(262)
Net (loss) income				(17,093)			(647)		(17,740)
Other comprehensive loss					(853)		65		(788)
Balance at Dec. 31, 2020	$ 4	$ 241,868		$ (158,066)	$ (2,279)		$ 394		$ 81,921
Balance (in shares) at Dec. 31, 2020	44,631,000								44,631,000