Consolidated Statements of Changes in Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Deficit	Treasury Stock	Accumulated Other Comprehensive Income (Loss)	Total Stockholders' Equity	Noncontrolling interest
Beginning balance (in shares) at Dec. 31, 2013		4,467,614
Beginning balance at Dec. 31, 2013	$ (99,480)	$ 38	$ 1,614	$ (95,476)	$ (5,656)	$ 0	$ (99,480)	$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock in connection with IPO, net of underwriting discounts (in shares)		11,500,000
Issuance of common stock in connection with IPO, net of underwriting discounts	209,990	$ 57	209,933				209,990
Stock-based compensation	3,095		3,095				3,095
Conversion of preferred stock warrants to common stock warrants upon IPO	4,912		4,912				4,912
Conversion of preferred stock to common stock (in shares)		47,457,356
Conversion of preferred stock to common stock	221,504	$ 237	221,267				221,504
Vesting of restricted stock units (in shares)		11,667
Vesting of restricted stock units	6		6				6
Issuance of common stock warrant	64		64				64
Exercise of stock options and warrants (in shares)		5,596,181
Exercise of stock options and warrants	2,106	$ 28	2,078				2,106
Accretion of dividends on redeemable convertible preferred stock	(12,884)			(12,884)			(12,884)
Net income (loss)	(18,708)			(18,708)			(18,708)
Ending balance (in shares) at Dec. 31, 2014		69,032,818
Ending balance at Dec. 31, 2014	310,605	$ 360	442,969	(127,068)	(5,656)	0	310,605	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	10,750		10,750				10,750
Vesting of restricted stock units (in shares)		88,124
Vesting of restricted stock units	41	$ 1	40				41
Accretion of dividends on redeemable convertible preferred stock	0
Investments by noncontrolling interests	7,873						0	7,873
Exercise of stock options (in shares)		747,224
Exercise of stock options	214	$ 4	210				214
Employee stock purchase plan (in shares)		202,732
Employee stock purchase plan	3,244	$ 1	3,243				3,244
Repurchases of common stock (in shares)		(10,690)
Repurchases of common stock	(187)				(187)		(187)
Other comprehensive Income	(678)					(372)	(372)	(306)
Other	(209)		(209)				(209)
Net income (loss)	$ (2,231)			(1,273)			(1,273)	(958)
Ending balance (in shares) at Dec. 31, 2015	70,060,208	70,060,208
Ending balance at Dec. 31, 2015	$ 329,422	$ 366	457,003	(128,341)	(5,843)	(372)	322,813	6,609
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	17,385		17,385				17,385
Accretion of dividends on redeemable convertible preferred stock	$ 0
Exercise of stock options (in shares)	559,034
Employee stock purchase plan (in shares)		456,008
Employee stock purchase plan	$ 2,943	$ 2	2,941				2,943
Repurchases of common stock (in shares)		(148,477)
Repurchases of common stock	(854)				(854)		(854)
Issuance of common stock through vesting of restricted stock units and option exercises (in shares)		1,237,969
Issuance of common stock through vesting of restricted stock units and option exercises	203	$ 6	197				203
Other comprehensive Income	(20)					(7)	(7)	(13)
Net income (loss)	$ (85,482)			(82,958)			(82,958)	(2,524)
Ending balance (in shares) at Dec. 31, 2016	71,605,708	71,605,708
Ending balance at Dec. 31, 2016	$ 263,597	$ 374	$ 477,526	$ (211,299)	$ (6,697)	$ (379)	$ 259,525	$ 4,072