Note 7 - Taxes on Income - Income Tax Provisions (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Current:
Federal		$ 2,846	$ 5,642	$ 6,527
Tax Cut and Jobs Act		265
State and local		647	628	519
Foreign		338
		4,096	6,270	7,046
Tax Cut and Jobs Act		1,336
Deferred Taxes:
Deferred tax provision (benefit)		1,899	(1,010)	(1,216)
Tax Cut and Jobs Act re-measurement		2,429
		4,328	(1,010)	(1,216)
	$ 5,000	$ 9,760	$ 5,260	$ 5,830