Note 8 - Loans and Related Allowance for Loan and Lease Losses - Past Due Financing Receivables (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Loans, current balance	$ 925,411	$ 915,131
Loans, past due	6,963	8,082
Loans, total	932,374	923,213
Financing Receivables, 30 to 59 Days Past Due [Member]
Loans, past due	3,821	5,501
Financing Receivables, 60 to 89 Days Past Due [Member]
Loans, past due	1,166	257
Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans, past due	1,976	2,324
Commercial And Industrial [Member]
Loans, current balance	99,201	99,633
Loans, past due	608	1,713
Loans, total	99,809	101,346
Commercial And Industrial [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member]
Loans, past due	175	1,607
Commercial And Industrial [Member] \| Financing Receivables, 60 to 89 Days Past Due [Member]
Loans, past due	366	29
Commercial And Industrial [Member] \| Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans, past due	67	77
Real Estate Construction Porfolio Segment [Member]
Loans, current balance	48,647	47,017
Loans, past due	40	0
Loans, total	48,687	47,017
Real Estate Construction Porfolio Segment [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member]
Loans, past due	40	0
Real Estate Construction Porfolio Segment [Member] \| Financing Receivables, 60 to 89 Days Past Due [Member]
Loans, past due	0	0
Real Estate Construction Porfolio Segment [Member] \| Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans, past due	0	0
Real Estate Mortgage Portfolio Segment [Member] \| Residential Loan [Member]
Loans, current balance	313,459	314,866
Loans, past due	3,397	3,291
Loans, total	316,856	318,157
Real Estate Mortgage Portfolio Segment [Member] \| Commercial Loans [Member]
Loans, current balance	445,861	434,879
Loans, past due	2,905	3,068
Loans, total	448,766	437,947
Real Estate Mortgage Portfolio Segment [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member] \| Residential Loan [Member]
Loans, past due	1,943	1,977
Real Estate Mortgage Portfolio Segment [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member] \| Commercial Loans [Member]
Loans, past due	1,652	1,907
Real Estate Mortgage Portfolio Segment [Member] \| Financing Receivables, 60 to 89 Days Past Due [Member] \| Residential Loan [Member]
Loans, past due	538	227
Real Estate Mortgage Portfolio Segment [Member] \| Financing Receivables, 60 to 89 Days Past Due [Member] \| Commercial Loans [Member]
Loans, past due	260	1
Real Estate Mortgage Portfolio Segment [Member] \| Financing Receivables, Equal to Greater than 90 Days Past Due [Member] \| Residential Loan [Member]
Loans, past due	916	1,087
Real Estate Mortgage Portfolio Segment [Member] \| Financing Receivables, Equal to Greater than 90 Days Past Due [Member] \| Commercial Loans [Member]
Loans, past due	993	1,160
Consumer Portfolio Segment [Member]
Loans, current balance	18,243	18,736
Loans, past due	13	10
Loans, total	18,256	18,746
Consumer Portfolio Segment [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member]
Loans, past due	11	10
Consumer Portfolio Segment [Member] \| Financing Receivables, 60 to 89 Days Past Due [Member]
Loans, past due	2	0
Consumer Portfolio Segment [Member] \| Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans, past due	$ 0	$ 0

Financing receivables that are current.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7A
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953401-111524

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Recorded Investment in financing receivables that are past due at the balance sheet date.

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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
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5074-111524

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