Note 5 - Accrued Expenses and Other Short Term Liabilities - Schedule of Accrued Expenses and Other Short Term Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Employees	$ 17,748	$ 12,306
Accrued expenses	9,507	6,777
Government authorities and other	14,006	8,293
Foreign exchange forward contract derivatives		479
Other short term liabilities	1,192	624
Total	$ 42,453	$ 28,479