Note 5 - Inventories (Details Textual) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Other Restructuring Costs					$ 7,400
Inventory Write-down	$ 0	$ 800	$ 0	$ 761
Systems [Member]
Inventory Write-down		$ 800			$ 1,500