Unaudited Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Cash flows from operating activities:
Net loss	$ (10,879)	$ (10,350)
Adjustments to reconcile net loss to net cash provided by operating activities:
Depreciation	622	497
Stock-based compensation	4,404	2,624
Changes in assets and liabilities:
Trade receivables	26,395	23,036
Prepaid expenses and other current assets	(2,497)	(648)
Trade payables	294	(1,910)
Accrued expenses and other short term liabilities	(6,421)	(4,580)
Severance pay	(219)	(4)
Deferred revenues	(3,203)	(2,702)
Other long term liabilities	(199)	(521)
Net cash provided by operating activities	8,297	5,442
Cash flows from investing activities:
Increase in short-term deposit	(4,757)	(250)
Increase in long-term deposits	(140)
Increase in restricted cash	(29)	(17)
Purchase of property and equipment	(1,498)	(722)
Net cash used in investing activities	(6,424)	(989)
Cash flows from financing activities:
Proceeds from employee stock plans, net	882	761
Net cash provided by financing activities	882	761
Increase in cash and cash equivalents	2,755	5,214
Cash and cash equivalents at beginning of period	48,315	49,241
Cash and cash equivalents at end of period	51,070	54,455
Supplemental disclosure of cash flow information:
Cash paid for income taxes	$ 20	$ 66