Note 4 - Loans and Allowance for Loan Losses - Loans (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Loans	$ 781,980	$ 769,319
Less: Allowance for loan losses	(7,639)	(7,499)
Loans, net	774,341	761,820
Residential Portfolio Segment [Member]
Loans	305,318	309,163
Commercial Real Estate Portfolio Segment [Member]
Loans	222,535	213,446
Commercial Real Estate Portfolio Segment [Member] \| Commercial Real Estate Owner Occupied [Member]
Loans	66,171	73,573
Commercial Real Estate Portfolio Segment [Member] \| Commercial Real Estate Nonowner Occupied [Member]
Loans	116,476	101,571
Commercial Real Estate Portfolio Segment [Member] \| Construction Loans [Member]
Loans	39,888	38,302
Commercial and Industrial Portfolio Segment [Member]
Loans	114,838	107,089
Consumer Portfolio Segment [Member]
Loans	139,289	139,621
Consumer Portfolio Segment [Member] \| Automobile Loan [Member]
Loans	68,446	68,626
Consumer Portfolio Segment [Member] \| Home Equity Loan [Member]
Loans	22,240	21,431
Consumer Portfolio Segment [Member] \| Other Consumer Loans [Member]
Loans	$ 48,603	$ 49,564

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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