Note 8 - Loans and Related Allowance for Loan and Lease Losses - Primary Segments of the Loan Portfolio (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Individually evaluated for impairment	$ 18,220	$ 12,109
Collectively evaluated for impairment	914,154	911,104
Total loans	932,374	923,213
Commercial And Industrial [Member]
Individually evaluated for impairment	8,884	3,627
Collectively evaluated for impairment	90,925	97,719
Total loans	99,809	101,346
Real Estate Construction Porfolio Segment [Member]
Individually evaluated for impairment		44
Collectively evaluated for impairment	48,687	46,973
Total loans	48,687	47,017
Real Estate Mortgage Portfolio Segment [Member] \| Residential Loan [Member]
Individually evaluated for impairment	2,716	2,824
Collectively evaluated for impairment	314,140	315,333
Total loans	316,856	318,157
Real Estate Mortgage Portfolio Segment [Member] \| Commercial Loans [Member]
Individually evaluated for impairment	6,617	5,610
Collectively evaluated for impairment	442,149	432,337
Total loans	448,766	437,947
Consumer Portfolio Segment [Member]
Individually evaluated for impairment	3	4
Collectively evaluated for impairment	18,253	18,742
Total loans	$ 18,256	$ 18,746

The balance of financing receivables that were collectively evaluated for impairment.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

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The balance of financing receivables that were individually evaluated for impairment.

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Amount before allowance and after 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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5074-111524

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