Note 10 - Leases (Details Textual) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Operating Lease, Weighted Average Remaining Lease Term (Year)	12 years 2 months 23 days	12 years 8 months 12 days	12 years 2 months 23 days	12 years 8 months 12 days
Operating Lease, Weighted Average Discount Rate, Percent	3.52%	3.50%	3.52%	3.50%
Operating Lease, Cost	$ 48,000	$ 48,000	$ 96,000	$ 96,000
Premises and Equipment [Member]
Operating Lease, Right-of-Use Asset	1,300,000	1,400,000	1,300,000	1,400,000
Other Liabilities [Member]
Operating Lease, Liability, Total	$ 1,469,000	$ 1,600,000	$ 1,469,000	$ 1,600,000