Note 3 - Loans and Allowance for Loan Losses - Allowance Related to Troubled Debt Restructurings (Details) - USD ($)	Sep. 30, 2019	Dec. 31, 2018
Related allowance	$ 2,234,000	$ 936,000
Commercial Portfolio Segment [Member]
Related allowance	1,734,000	489,000
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]
Related allowance	729,000	126,000
Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member]
Related allowance	0	0
Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member]
Related allowance	1,005,000	363,000
Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member]
Related allowance	0	0
Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member]
Related allowance	0	0
Retail Portfolio Segment [Member]
Related allowance	500,000	447,000
Retail Portfolio Segment [Member] | Home Equity and Other [Member]
Related allowance	402,000	337,000
Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member]
Related allowance	$ 98,000	$ 110,000