Condensed Consolidated Statements of Operations (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Income Statement [Abstract]
Revenue	$ 54,975	$ 40,670	$ 103,995	$ 78,107
Cost of revenue	7,397	4,776	13,517	9,185
Gross profit	47,578	35,894	90,478	68,922
Operating expenses
Research and development	7,973	6,918	14,685	14,309
Sales and marketing	31,053	22,567	58,763	43,135
General and administrative	7,448	6,352	14,125	17,872
Amortization of acquired intangibles	322	180	525	359
Total operating expenses	46,796	36,017	88,098	75,675
(Loss) income from operations	782	(123)	2,380	(6,753)
Interest income, net	149	155	260	320
Other (expense) income	224	(198)	196	454
(Loss) income before income taxes	1,155	(166)	2,836	(5,979)
(Provision for) benefit from income taxes	175	(1,194)	(502)	(1,188)
Net (loss) income	$ 1,330	$ (1,360)	$ 2,334	$ (7,167)
Net (loss) income per share:
Basic	$ 0.05	$ (0.06)	$ 0.10	$ (0.29)
Diluted	$ 0.05	$ (0.06)	$ 0.09	$ (0.29)
Weighted average shares outstanding:
Basic	24,425,081	24,262,417	24,134,686	24,485,429
Diluted	25,159,340	24,262,417	24,889,730	24,485,429