Note 4 - Loans and Allowance for Loan Losses - Nonaccrual Loans and Loans Past Due 90 Days or More and Still Accruing (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Loans past due 90 days and still accruing	$ 936	$ 1,067
Nonaccrual	8,252	8,677
Residential Portfolio Segment [Member]
Loans past due 90 days and still accruing	242	19
Nonaccrual	6,090	6,661
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Owner Occupied [Member]
Loans past due 90 days and still accruing	151
Nonaccrual	139	470
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Nonowner Occupied [Member]
Loans past due 90 days and still accruing		362
Nonaccrual	765	574
Commercial Real Estate Portfolio Segment [Member] | Construction Loans [Member]
Loans past due 90 days and still accruing		66
Nonaccrual	187	416
Commercial and Industrial Portfolio Segment [Member]
Loans past due 90 days and still accruing	4	31
Nonaccrual	515	228
Consumer Portfolio Segment [Member] | Automobile Loan [Member]
Loans past due 90 days and still accruing	234	270
Nonaccrual	66	59
Consumer Portfolio Segment [Member] | Home Equity Loan [Member]
Loans past due 90 days and still accruing		91
Nonaccrual	407	183
Consumer Portfolio Segment [Member] | Other Consumer Loans [Member]
Loans past due 90 days and still accruing	305	228
Nonaccrual	$ 83	$ 86