Note 4 - Loans - Outstanding Loan Balances (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Gross loans	$ 900,420	$ 879,835
Deferred fees and costs	1,713	1,710
Loans, net of deferred fees and costs	902,133	881,545
Allowance for loan and lease losses	(12,295)	(11,925)
Net loans	889,838	869,620
Commercial Portfolio Segment [Member]
Gross loans	137,870	142,405
Commercial Real Estate Portfolio Segment [Member]
Gross loans	613,201	585,593
Commercial Real Estate Portfolio Segment [Member] \| Construction Loans [Member]
Gross loans	14,723	15,902
Commercial Real Estate Portfolio Segment [Member] \| Commercial Non-owner Occupied [Member]
Gross loans	405,192	377,668
Commercial Real Estate Portfolio Segment [Member] \| Commercial Owner Occupied Loan [Member]
Gross loans	193,286	192,023
Residential Portfolio Segment [Member]
Gross loans	101,192	101,912
Residential Portfolio Segment [Member] \| Real Estate Loan [Member] \| Individual Tax Identification Number Loan [Member]
Gross loans	40,425	41,188
Residential Portfolio Segment [Member] \| Real Estate Loan [Member] \| Mortgage Receivable [Member]
Gross loans	30,247	30,377
Residential Portfolio Segment [Member] \| Home Equity Loan [Member]
Gross loans	30,520	30,347
Consumer Portfolio Segment [Member]
Gross loans	$ 48,157	$ 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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