Note 12 - Leases - Lease Cost and Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Operating lease cost	$ 565,000	$ 517,000
Short-term lease cost	18,000	119,000
Total lease cost	583,000	636,000
Operating cash flows from operating leases	$ 543,000	$ 459,000
Weighted -average remaining lease term - operating leases (in years) (Year)	9 years	10 years
Weighted -average discount rate - operating leases	3.48%	3.48%