Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Income Statement [Abstract]
Total revenues	$ 34,873	$ 31,488	$ 96,175	$ 78,161
Costs and expenses
Cost of sales (excludes amortization of intangible assets of $1,590, $1,571, $3,161 and $3,142, respectively)	15,493	15,902	36,605	36,149
Research and development	9,105	8,127	17,156	17,208
Sales and marketing	11,592	9,393	22,981	19,320
General and administrative	6,290	5,843	16,150	13,070
Amortization of intangible assets from acquired businesses and technology	2,218	2,208	4,419	4,416
Total costs and expenses	44,698	41,473	97,311	90,163
Operating loss	(9,825)	(9,985)	(1,136)	(12,002)
Interest expense, net	(3,061)	(372)	(5,956)	(731)
Loss before benefit for income taxes	(12,886)	(10,357)	(7,092)	(12,733)
Benefit for income taxes	(3,955)	(3,449)	(2,152)	(4,313)
Net loss	$ (8,931)	$ (6,908)	$ (4,940)	$ (8,420)
Basic and diluted loss per share	$ (0.26)	$ (0.20)	$ (0.14)	$ (0.25)
Weighted shares used in basic and diluted per share calculation	34,597	34,347	34,611	34,271