Condensed Consolidated Statements of Operations (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Income Statement [Abstract]
Revenue	$ 89,465	$ 64,431	$ 153,934	$ 115,989
Cost of revenue	27,521	18,116	45,750	32,494
Gross profit	61,944	46,315	108,184	83,495
Operating expenses:
Research and development	6,403	5,809	12,606	11,889
Sales and marketing	50,293	32,199	90,948	56,605
General and administrative	8,774	6,654	19,320	15,042
Total operating expenses	65,470	44,662	122,874	83,536
Income (loss) from operations	(3,526)	1,653	(14,690)	(41)
Interest income (expense), net	(20)	13	(56)	26
Other income (expense), net	1,409	(445)	2,055	(865)
Income (loss) before income taxes	(2,137)	1,221	(12,691)	(880)
Provision for income taxes	2,765	43	2,081	71
Net income (loss)	$ (4,902)	$ 1,178	$ (14,772)	$ (951)
Basic net income (loss) per share:
Net income (loss) per share, basic (usd per share)	$ (0.12)	$ 0.03	$ (0.38)	$ (0.02)
Weighted average shares of common stock outstanding used in computing net income (loss) per share, basic (shares)	39,493,665	38,649,873	39,391,259	38,517,817
Diluted net income (loss) per share:
Net income (loss) per share, diluted (usd per share)	$ (0.12)	$ 0.03	$ (0.38)	$ (0.02)
Weighted average shares of common stock outstanding used in computing net income (loss) per share, diluted (shares)	39,493,665	41,641,660	39,391,259	38,517,817