Consolidated Statements of Operations (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Revenue:
Total revenue	$ 78,959	$ 58,441	$ 152,144	$ 112,956
Cost of revenue:
Total cost of revenue	22,181	17,393	42,154	33,987
Total gross profit	56,778	41,048	109,990	78,969
Operating expenses:
Research and development	19,626	16,082	37,491	32,804
Sales and marketing	38,172	31,157	73,310	60,209
General and administrative	11,160	8,149	21,113	16,881
Total operating expenses	68,958	55,388	131,914	109,894
Loss from operations	(12,180)	(14,340)	(21,924)	(30,925)
Other income (expense), net:
Interest income	1,582	464	3,313	707
Interest expense	(3,312)	0	(6,541)	(2)
Other income (expense), net	(29)	(326)	(235)	(248)
Loss before income taxes	(13,939)	(14,202)	(25,387)	(30,468)
Provision for (benefit from) income taxes	(519)	131	(294)	226
Net loss	$ (13,420)	$ (14,333)	$ (25,093)	$ (30,694)
Net loss per share, basic and diluted (in dollars per share)	$ (0.28)	$ (0.31)	$ (0.52)	$ (0.67)
Weighted-average common shares outstanding, basic and diluted (in shares)	48,451,562	46,279,947	48,141,474	45,746,513
Product [Member]
Revenue:
Total revenue	$ 63,207	$ 39,043	$ 119,495	$ 74,322
Cost of revenue:
Total cost of revenue	14,556	9,650	27,041	18,086
Maintenance and Support [Member]
Revenue:
Total revenue	9,372	10,610	18,929	21,363
Cost of revenue:
Total cost of revenue	2,081	2,007	3,965	3,856
Professional Services [Member]
Revenue:
Total revenue	6,380	8,788	13,720	17,271
Cost of revenue:
Total cost of revenue	$ 5,544	$ 5,736	$ 11,148	$ 12,045