Note 9 - Information About Geographic Areas and Operating Segments - Revenue and Long-lived Assets by Geographic Area (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Total revenue	$ 10,420	$ 14,641	$ 36,073	$ 43,917
Total long-lived assets	1,994		1,994		$ 2,533
North America [Member]
Total revenue	8,919	12,714	30,449	37,619
Total long-lived assets	1,823		1,823		2,016
Asia [Member]
Total revenue	716	1,586	3,805	4,735
Total long-lived assets					177
Europe [Member]
Total revenue	785	$ 341	1,819	$ 1,563
Total long-lived assets	$ 171		$ 171		$ 340