Consolidated Statements of Stockholders' Equity - 3 months ended Mar. 31, 2016 - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit
Beginning Balance (in shares) at Dec. 31, 2015	46,600	46,600
Beginning Balance at Dec. 31, 2015	$ 278,101	$ 0	$ 358,406	$ (15)	$ (80,290)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of common stock options (in shares)		941
Exercise of common stock options	6,718		6,718
Restricted stock awards, net (in shares)		485
Issuance of common stock related to RSU vesting (in shares)		7
Stock-based compensation	8,597		8,597
Foreign exchange translation adjustment	27			27
Accumulated Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax	64			64
Net income	$ 2,284				2,284
Ending Balance (in shares) at Mar. 31, 2016	48,033	48,033
Ending Balance at Mar. 31, 2016	$ 295,791	$ 0	$ 373,721	$ 76	$ (78,006)