Note 4 - Bank Acceptance Notes - Bank Acceptance Notes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Balance as of beginning of period	$ 904
Balance as of end of period		$ 904
Bankers Acceptance [Member]
Balance as of beginning of period	904	3,360
Received from customers		1,985
Converted to cash	(888)	(3,508)
Paid to suppliers		(1,162)
Foreign exchange impact	(16)	229
Balance as of end of period		$ 904