Note 12 - Segment Information (Details Textual) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)
Number of Operating Segments			2
Number of Reportable Segments			2
Intersegment Eliminations [Member]
Revenue from Contract with Customer, Including Assessed Tax	$ 0	$ 1,300	$ 2,200	$ 3,800