CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Revenue:
Total revenue, net		$ 35,500	$ 35,910	$ 74,545	$ 71,400
Cost of revenue:
Total cost of revenue		12,761	14,163	27,234	28,273
Gross profit		22,739	21,747	47,311	43,127
Operating expenses:
Sales and marketing	[1]	7,683	8,889	18,155	18,104
Research and development	[1]	13,043	14,487	26,865	30,212
General and administrative	[1]	6,340	7,010	12,916	14,303
Goodwill impairment		0	0	50,300	0
Total operating expenses		27,066	30,386	108,236	62,619
Operating loss		(4,327)	(8,639)	(60,925)	(19,492)
Other income, net		123	258	386	572
Net loss		$ (4,204)	$ (8,381)	$ (60,539)	$ (18,920)
Net loss per share, basic and diluted (in usd per share)		$ (0.03)	$ (0.06)	$ (0.41)	$ (0.13)
Weighted-average shares used to compute basic and diluted net loss per share (in shares)		150,078	144,572	149,475	143,790
Subscription
Revenue:
Total revenue, net		$ 34,289	$ 33,964	$ 72,672	$ 67,770
Cost of revenue:
Total cost of revenue	[1]	8,819	8,234	19,051	16,400
Professional services and other
Revenue:
Total revenue, net		1,211	1,946	1,873	3,630
Cost of revenue:
Total cost of revenue	[1]	$ 3,942	$ 5,929	$ 8,183	$ 11,873

[1] Includes stock-based compensation expense as follows:  Three Months Ended June 30,Six Months Ended June 30, 2020201920202019Cost of revenue:Cost of subscription$205  $196  $374  $415  Cost of professional services and other144  236  260  501  Sales and marketing748  662  1,420  1,289  Research and development1,314  1,733  2,477  3,437  General and administrative858  2,030  1,924  3,192