Note 4 - Loans - Outstanding Loan Balances (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Gross loans	$ 927,480	$ 879,835
Deferred fees and costs	1,757	1,710
Loans, net of deferred fees and costs	929,237	881,545
Allowance for loan and lease losses	(12,392)	(11,925)
Net loans	916,845	869,620
Commercial Portfolio Segment [Member]
Gross loans	132,091	142,405
Commercial Real Estate Portfolio Segment [Member]
Gross loans	647,350	585,593
Commercial Real Estate Portfolio Segment [Member] \| Construction Loans [Member]
Gross loans	20,496	15,902
Commercial Real Estate Portfolio Segment [Member] \| Commercial Non-owner Occupied [Member]
Gross loans	431,246	377,668
Commercial Real Estate Portfolio Segment [Member] \| Commercial Owner Occupied Loan [Member]
Gross loans	195,608	192,023
Residential Portfolio Segment [Member]
Gross loans	100,539	101,912
Residential Portfolio Segment [Member] \| Real Estate Loan [Member] \| Individual Tax Identification Number Loan [Member]
Gross loans	38,353	41,188
Residential Portfolio Segment [Member] \| Real Estate Loan [Member] \| Mortgage Receivable [Member]
Gross loans	33,473	30,377
Residential Portfolio Segment [Member] \| Home Equity Loan [Member]
Gross loans	28,713	30,347
Consumer Portfolio Segment [Member]
Gross loans	$ 47,500	$ 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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