Note 14 - Total Sales, Based Upon the Country to Which Sales to External Customers Were Made (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
UNITED STATES
Revenue, Net	$ 20,872	$ 19,836	$ 19,052
Europe [Member]
Revenue, Net	23,673	26,324	23,966
Asia [Member]
Revenue, Net	12,762	14,166	10,481
Other Region [Member]
Revenue, Net	3,917	4,149	3,609
Total Foreign Sales [Member]
Revenue, Net	40,352	44,639	38,056
Revenue, Net	$ 61,224	$ 64,475	$ 57,108