Note 21 - Employee Benefit Plan (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent	60.00%
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay	4.00%	3.00%	2.00%
Defined Contribution Plan, Employer Discretionary Contribution Amount	$ 1,600	$ 1,400	$ 1,000
Deposits And Other Assets Noncurrent	18,209	21,599
Severance Costs	3,000	3,200	2,300
Gain (Loss) Of Severance Fund	1,100	1,800	$ 300
Israeli Severance Funds [Member]
Deposits And Other Assets Noncurrent	$ 10,600	$ 13,900