Note 4 - Loans - Outstanding Loan Balances (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Gross loans	$ 936,816	$ 879,835
Deferred fees and costs	1,763	1,710
Loans, net of deferred fees and costs	938,579	881,545
Allowance for loan and lease losses	(12,388)	(11,925)
Net loans	926,191	869,620
Commercial Portfolio Segment [Member]
Gross loans	139,670	142,405
Commercial Real Estate Portfolio Segment [Member]
Gross loans	647,792	585,593
Commercial Real Estate Portfolio Segment [Member] \| Construction Loans [Member]
Gross loans	21,292	15,902
Commercial Real Estate Portfolio Segment [Member] \| Commercial Non-owner Occupied [Member]
Gross loans	427,088	377,668
Commercial Real Estate Portfolio Segment [Member] \| Commercial Owner Occupied Loan [Member]
Gross loans	199,412	192,023
Residential Portfolio Segment [Member]
Gross loans	101,694	101,912
Residential Portfolio Segment [Member] \| Real Estate Loan [Member] \| Individual Tax Identification Number Loan [Member]
Gross loans	39,424	41,188
Residential Portfolio Segment [Member] \| Real Estate Loan [Member] \| Mortgage Receivable [Member]
Gross loans	33,391	30,377
Residential Portfolio Segment [Member] \| Home Equity Loan [Member]
Gross loans	28,879	30,347
Consumer Portfolio Segment [Member]
Gross loans	$ 47,660	$ 49,925

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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