Note 13 - Commitments and Contingencies (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Jan. 01, 2019
Operating Leases, Rent Expense, Total	$ 1,096,000	$ 1,171,000
Operating Lease, Weighted Average Remaining Lease Term			7 years 328 days
Operating Lease, Weighted Average Discount Rate, Percent			3.12%
Operating Lease, Right-of-Use Asset	$ 4,312,000	$ 0
Interest Payable and Other Liabilities [Member]
Operating Lease, Liability, Total			$ 5,246,000
Interest Receivable and Other Assets [Member]
Operating Lease, Right-of-Use Asset			$ 4,817,000