CONSOLIDATED STATEMENTS OF REDEEMABLE CONVERTIBLE PREFERRED STOCK AND STOCKHOLDERS' EQUITY (DEFICIT) - USD ($) $ in Thousands	Common Stock	Treasury Stock	Additional Paid-In Capital	Accumulated Deficit	Accumulated Other Comprehensive (Loss) Income	Total
Balance at Dec. 31, 2012			$ 12,988	$ (105,587)	$ (4)	$ (92,603)
Balance (in shares) at Dec. 31, 2012	2,490,870
Increase (Decrease) in Stockholders' Equity
Net income (loss)				3,503		3,503
Other comprehensive income (loss)					15	15
Stock-based compensation			3,760			3,760
Issuance of common stock options in connection with a business acquisition			174			174
Conversion of redeemable convertible preferred stock into common stock	$ 2		116,311			116,313
Conversion of redeemable convertible preferred stock into common stock (in shares)	15,293,960
Issuance of common stock, net of issuance costs			65,556			65,556
Issuance of common stock, net of issuance costs (in shares)	4,600,000
Reclassification of redeemable convertible preferred stock warrant liability upon conversion to common stock warrant						1,310
Issuance of common stock upon net exercise of common stock warrants (in shares)	293,232
Reclassification of redeemable convertible preferred stock warrant liability upon conversion to preferred stock			1,310
Issuance of common stock upon exercise of stock options			446			446
Issuance of common stock upon exercise of stock options (in shares)	107,042
Balance at Dec. 31, 2013	$ 2		200,545	(102,084)	11	98,474
Balance (in shares) at Dec. 31, 2013	22,785,104
Increase (Decrease) in Stockholders' Equity
Net income (loss)				8,156		8,156
Other comprehensive income (loss)					(171)	(171)
Excess tax benefit from exercise of options for common stock			91			91
Stock-based compensation			5,341			5,341
Issuance of common stock upon net exercise of common stock warrants			6,411			6,411
Issuance of common stock upon net exercise of common stock warrants (in shares)	7,763
Issuance of common stock upon exercise of stock options (in shares)	1,512,514
Balance at Dec. 31, 2014	$ 2		212,388	(93,928)	(160)	118,302
Balance (in shares) at Dec. 31, 2014	24,305,381
Increase (Decrease) in Stockholders' Equity
Net income (loss)				(1,652)		(1,652)
Other comprehensive income (loss)					(579)	(579)
Stock-based compensation			7,034			7,034
Issuance of common stock upon exercise of stock options			1,360			1,360
Issuance of common stock upon exercise of stock options (in shares)	285,387
Repurchase of common stock for treasury		$ (9,020)				(9,020)
Repurchase of common stock for treasury (in shares)	(1,154,480)	1,154,480
Balance at Dec. 31, 2015	$ 2	$ (9,020)	$ 220,782	$ (95,580)	$ (739)	$ 115,445
Balance (in shares) at Dec. 31, 2015	23,436,288	1,154,480