Consolidated Statements of Operations and Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Income Statement [Abstract]
Revenue	$ 48,379	$ 37,386	$ 136,808	$ 102,920
Cost of revenue	14,725	11,122	43,659	29,197
Gross profit	33,654	26,264	93,149	73,723
Operating expenses:
Sales and marketing	17,841	14,571	58,644	44,215
Research and development	5,424	3,875	15,338	10,348
General and administrative	9,648	6,422	26,998	16,072
Intangible asset amortization, excluding cost of revenue	680	110	1,492	282
Total operating expenses	33,593	24,978	102,472	70,917
Income (loss) from operations	61	1,286	(9,323)	2,806
Interest income	679	450	1,800	1,091
Other income (loss)	0	(434)	(426)	(434)
Income (loss) from operations before income taxes	740	1,302	(7,949)	3,463
(Benefit from) provision for income taxes	(41)	231	(703)	(241)
Net income (loss)	$ 781	$ 1,071	$ (7,246)	$ 3,704
Net income (loss) per common share:
Basic (USD per share)	$ 0.02	$ 0.03	$ (0.17)	$ 0.09
Diluted (USD per share)	$ 0.02	$ 0.02	$ (0.17)	$ 0.09
Weighted average common shares outstanding-basic (shares)	41,723,667	41,103,502	41,512,189	40,910,381
Weighted average common shares outstanding-diluted (shares)	43,481,392	43,151,239	41,512,189	43,174,201
Other comprehensive income (loss):
Foreign currency translation gain	$ (87)	$ 0	$ (36)	$ 0
Comprehensive income (loss)	$ 694	$ 1,071	$ (7,282)	$ 3,704