Note 8 - Loans and Related Allowance for Loan and Lease Losses - Major Classifications of Net Loans (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016
Loans	$ 943,674		$ 923,213
Less: Allowance for loan and lease losses	(7,502)	$ (7,551)	(7,190)	$ (6,605)	$ (6,720)	$ (6,598)
Net loans	936,172		916,023
Commercial And Industrial [Member]
Loans	101,975		101,346
Less: Allowance for loan and lease losses	(1,180)	(1,256)	(999)	(613)	(616)	(448)
Real Estate Construction Porfolio Segment [Member]
Loans	45,647		47,017
Less: Allowance for loan and lease losses	(89)	(92)	(313)	(202)	(186)	(172)
Real Estate Mortgage Portfolio Segment [Member] \| Residential Loan [Member]
Loans	320,858		318,157
Less: Allowance for loan and lease losses	(1,743)	(1,782)	(1,760)	(1,767)	(2,523)	(2,818)
Real Estate Mortgage Portfolio Segment [Member] \| Commercial Loans [Member]
Loans	457,050		437,947
Less: Allowance for loan and lease losses	(4,361)	(4,323)	(4,036)	(4,012)	(3,378)	(3,135)
Consumer Portfolio Segment [Member]
Loans	18,144		18,746
Less: Allowance for loan and lease losses	$ (129)	$ (98)	$ (82)	$ (11)	$ (17)	$ (25)

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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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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