Consolidated Statements of Stockholders' Equity (unaudited) - 6 months ended Jun. 30, 2018 - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Deficit	Accumulated Other Comprehensive Income (Loss)
Balance at Dec. 31, 2017	$ 55,991	$ 28	$ 164,995	$ (109,252)	$ 220
Balance, shares at Dec. 31, 2017		28,330,460
Cumulative effect of adoption of ASU 2014-09, net of taxes	9,097			9,097
Stock-based compensation	16,716		16,716
Vesting of restricted stock units		444,248
Restricted stock units withheld to settle employee tax withholding liability	(3,772)		(3,772)
Restricted stock units withheld to settle employee tax withholding liability, shares		(81,097)
Exercise of stock options	$ 5,835	$ 1	5,834
Exercise of stock options, shares	521,563	521,563
Issuance of shares under employee stock purchase plan	$ 881		881
Issuance of shares under employee stock purchase plan, shares		44,193
Other comprehensive income	(2,651)				(2,651)
Net loss	(29,260)			(29,260)
Balance at Jun. 30, 2018	$ 52,837	$ 29	$ 184,654	$ (129,415)	$ (2,431)
Balance, shares at Jun. 30, 2018		29,259,367