Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Cash flows from operating activities:
Net loss	$ (78,764)	$ (28,578)	$ (13,844)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:
Depreciation	6,321	4,156	3,328
Stock-based compensation	46,139	34,961	19,835
Amortization of deferred commissions	13,630	13,185	12,591
Amortization of operating lease right-of-use asset	9,023
Capital loss (gain) from sale of fixed assets	45	(27)	(20)
Changes in assets and liabilities:
Trade receivables	8,173	(7,627)	(21,735)
Prepaid expenses and other current assets	(1,225)	(1,932)	(3,317)
Deferred commissions	(19,132)	(15,308)	(14,742)
Other long term assets	81	(270)	0
Trade payables	(1,623)	1,985	(653)
Accrued expenses and other short-term liabilities	(886)	9,910	14,453
Deferred revenues	7,219	14,115	20,860
Other long term liabilities	316	(1,025)	(405)
Net cash provided by (used in) operating activities	(10,683)	23,545	16,351
Cash flows from investing activities:
Decrease (increase) in short-term deposits	60,466	(30,280)	25,329
Increase in marketable securities	(1,761)	(39)	(39,731)
Increase in long-term deposits	(21)	(313)	(305)
Proceeds from sale of property and equipment	11	27	20
Purchase of property and equipment	(25,392)	(9,583)	(5,314)
Net cash provided by (used in) investing activities	33,303	(40,188)	(20,001)
Cash flows from financing activities:
Proceeds (withholdings) from employee stock plans, net	(2,398)
Proceeds (withholdings) from employee stock plans, net		8,114	12,083
Net cash provided by (used in) financing activities	(2,398)	8,114	12,083
Increase (decrease) in cash, cash equivalents and restricted cash	20,222	(8,529)	8,433
Cash, cash equivalents and restricted cash at beginning of period	48,707	57,236	48,803
Cash, cash equivalents and restricted cash at end of period	68,929	48,707	57,236
Supplemental disclosure of cash flow information:
Cash paid for income taxes	3,955	$ 710	$ 469
Net lease liabilities arising from obtaining right-of-use assets	$ 10,252