Note 8 - Loans and Related Allowance for Loan and Lease Losses - Major Classifications of Net Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017	Mar. 31, 2017	Dec. 31, 2016
Financing Receivable Gross	$ 932,374	$ 923,213
Less: Allowance for loan and lease losses	(7,551)	(7,190)	$ (6,720)	$ (6,598)
Net loans	924,823	916,023
Commercial And Industrial [Member]
Financing Receivable Gross	99,809	101,346
Less: Allowance for loan and lease losses	(1,256)	(999)	(616)	(448)
Real Estate Construction Porfolio Segment [Member]
Financing Receivable Gross	48,687	47,017
Less: Allowance for loan and lease losses	(92)	(313)	(186)	(172)
Real Estate Mortgage Portfolio Segment [Member] \| Residential Loan [Member]
Financing Receivable Gross	316,856	318,157
Less: Allowance for loan and lease losses	(1,782)	(1,760)	(2,523)	(2,818)
Real Estate Mortgage Portfolio Segment [Member] \| Commercial Loans [Member]
Financing Receivable Gross	448,766	437,947
Less: Allowance for loan and lease losses	(4,323)	(4,036)	(3,378)	(3,135)
Consumer Portfolio Segment [Member]
Financing Receivable Gross	18,256	18,746
Less: Allowance for loan and lease losses	$ (98)	$ (82)	$ (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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