Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Net cash provided by operating activities	$ 3,091	$ 4,760
Investing activities
Purchases of marketable securities	(15,375)	(26,112)
Proceeds from maturity of marketable securities	9,388	21,500
Investment in short-term deposits	(3,000)
Proceeds from sales of marketable securities	8,578	7,987
Purchases of property and equipment	(625)	(1,012)
Increase in restricted deposits	(20)
Net cash provided by (used in) investing activities	(1,054)	2,363
Financial activities
Purchase of treasury stock	(2,629)	(3,737)
Issuance of treasury stock upon exercise of stock options	681	666
Net cash used in financing activities	(1,948)	(3,071)
Increase in cash and cash equivalents	89	4,052
Erosion due to exchange rate differences	21	52
Cash and cash equivalents at the beginning of the period	17,752	13,704
Cash and cash equivalents at the end of the period	$ 17,862	$ 17,808