CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Revenues, net	$ 24,013	$ 26,327	$ 76,954	$ 79,515
Cost of revenues	8,668	10,375	26,752	30,683
Gross profit	15,345	15,952	50,202	48,832
Operating expenses
Sales and marketing	7,581	10,835	25,973	36,056
Research and development	6,268	8,162	21,321	25,840
General and administrative	4,735	5,882	14,722	17,257
Total operating expenses	18,584	24,879	62,016	79,153
Loss from operations	(3,239)	(8,927)	(11,814)	(30,321)
Interest expense, net	(39)	(63)	(91)	(82)
Other income (expenses), net	188	(214)	632	(134)
Loss before benefit from (provision for) income taxes	(3,090)	(9,204)	(11,273)	(30,537)
Benefit from (provision for) income taxes	37	(300)	(611)	(674)
Net loss	(3,053)	(9,504)	(11,884)	(31,211)
Foreign currency translation adjustments	(15)	(13)	86	(626)
Comprehensive loss	$ (3,068)	$ (9,517)	$ (11,798)	$ (31,837)
Net loss per share available to common stockholders, basic and diluted	$ (0.08)	$ (0.26)	$ (0.31)	$ (0.86)
Weighted-average shares used to compute net loss per share available to common stockholders, basic and diluted	38,520	36,953	38,190	36,367
Amortization of intangible assets is allocated as follows (Note 5):
Amortization of intangible assets	$ 730	$ 826	$ 2,350	$ 2,308
Cost of Revenues [Member]
Stock-based compensation is allocated as follows (Note 9):
Allocation of stock-based compensation	285	249	1,015	800
Amortization of intangible assets is allocated as follows (Note 5):
Amortization of intangible assets	246	271	780	762
Restructuring related expenses are allocated as follows (Note 3):
Restructuring related expenses	24	105	175	105
Sales and Marketing [Member]
Stock-based compensation is allocated as follows (Note 9):
Allocation of stock-based compensation	162	435	1,083	2,104
Amortization of intangible assets is allocated as follows (Note 5):
Amortization of intangible assets	223	247	711	674
Restructuring related expenses are allocated as follows (Note 3):
Restructuring related expenses	2	659	213	659
Research and Development [Member]
Stock-based compensation is allocated as follows (Note 9):
Allocation of stock-based compensation	852	1,864	4,149	5,831
Amortization of intangible assets is allocated as follows (Note 5):
Amortization of intangible assets	246	271	780	763
Restructuring related expenses are allocated as follows (Note 3):
Restructuring related expenses	(4)	53	44	53
General and Administrative [Member]
Stock-based compensation is allocated as follows (Note 9):
Allocation of stock-based compensation	532	1,058	2,345	3,305
Amortization of intangible assets is allocated as follows (Note 5):
Amortization of intangible assets	15	37	79	109
Restructuring related expenses are allocated as follows (Note 3):
Restructuring related expenses	$ 2	$ 264	$ 17	$ 264