Note 5 - Leases (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Finance Lease, Principal Payments	$ 93	$ 111
Operating Lease, Weighted Average Remaining Lease Term (Year)	1 year 146 days
Finance Lease, Weighted Average Remaining Lease Term (Year)	3 years 182 days
Operating Lease, Weighted Average Discount Rate, Percent	4.10%
Finance Lease, Weighted Average Discount Rate, Percent	5.20%
Operating Lease, Expense	$ 1,500	$ 1,500