Note 11 - Leases (Details Textual) - USD ($)	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Operating Lease, Weighted Average Remaining Lease Term (Year)	12 years 306 days	13 years 164 days
Operating Lease, Weighted Average Discount Rate, Percent	3.49%	3.47%
Operating Lease, Cost	$ 48,000	$ 49,000
Premises and Equipment [Member]
Operating Lease, Right-of-Use Asset	1,500,000	1,600,000
Other Liabilities [Member]
Operating Lease, Liability, Total	$ 1,669,000	$ 1,800,000