Condensed Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Income Statement [Abstract]
Revenue	$ 35,262	$ 26,081	$ 100,830	$ 73,104
Cost of revenue	10,972	9,596	31,657	27,098
Gross profit	24,290	16,485	69,173	46,006
Operating expenses:
Sales and marketing	14,599	12,389	41,534	33,926
Research and development	7,747	6,012	22,758	16,213
General and administrative	7,346	7,256	22,550	21,298
Change in fair value of contingent consideration	0	0	0	(11)
Total operating expenses	29,692	25,657	86,842	71,426
Loss from operations	(5,402)	(9,172)	(17,669)	(25,420)
Change in fair value of preferred stock warrant	0	0	0	(25)
Interest expense, net	(261)	(335)	(865)	(612)
Other expense, net	(90)	(20)	(226)	(112)
Loss before provision for income taxes	(5,753)	(9,527)	(18,760)	(26,169)
Provision for income taxes	142	101	279	169
Net loss	(5,895)	(9,628)	(19,039)	(26,338)
Accretion of redeemable convertible preferred stock	0	0	0	(9,862)
Deemed dividend—preferred stock modification	0	0	0	1,748
Net loss attributable to common stockholders	$ (5,895)	$ (9,628)	$ (19,039)	$ (34,452)
Net loss per share attributable to common stockholders, basic and diluted (in dollars per share)	$ (0.15)	$ (0.25)	$ (0.48)	$ (1.57)
Weighted-average shares used to compute net loss per share attributable to common stockholders, basic and diluted (in shares)	39,965,454	39,181,118	39,708,257	21,976,654