Note 8 - Loans and Related Allowance for Loan and Lease Losses - Past Due Loans (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Loans, current balance	$ 937,475	$ 915,131
Loans, past due	6,199	8,082
Loans	943,674	923,213
Financing Receivables, 30 to 59 Days Past Due [Member]
Loans, past due	2,751	5,501
Financing Receivables, 60 to 89 Days Past Due [Member]
Loans, past due	904	257
Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans, past due	2,544	2,324
Commercial And Industrial [Member]
Loans, current balance	101,459	99,633
Loans, past due	516	1,713
Loans	101,975	101,346
Commercial And Industrial [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member]
Loans, past due	50	1,607
Commercial And Industrial [Member] \| Financing Receivables, 60 to 89 Days Past Due [Member]
Loans, past due	45	29
Commercial And Industrial [Member] \| Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans, past due	421	77
Real Estate Construction Porfolio Segment [Member]
Loans, current balance	45,647	47,017
Loans, past due		0
Loans	45,647	47,017
Real Estate Construction Porfolio Segment [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member]
Loans, past due		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	316,239	314,866
Loans, past due	4,619	3,291
Loans	320,858	318,157
Real Estate Mortgage Portfolio Segment [Member] \| Commercial Loans [Member]
Loans, current balance	456,006	434,879
Loans, past due	1,044	3,068
Loans	457,050	437,947
Real Estate Mortgage Portfolio Segment [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member] \| Residential Loan [Member]
Loans, past due	2,620	1,977
Real Estate Mortgage Portfolio Segment [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member] \| Commercial Loans [Member]
Loans, past due	67	1,907
Real Estate Mortgage Portfolio Segment [Member] \| Financing Receivables, 60 to 89 Days Past Due [Member] \| Residential Loan [Member]
Loans, past due	853	227
Real Estate Mortgage Portfolio Segment [Member] \| Financing Receivables, 60 to 89 Days Past Due [Member] \| Commercial Loans [Member]
Loans, past due		1
Real Estate Mortgage Portfolio Segment [Member] \| Financing Receivables, Equal to Greater than 90 Days Past Due [Member] \| Residential Loan [Member]
Loans, past due	1,146	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	977	1,160
Consumer Portfolio Segment [Member]
Loans, current balance	18,124	18,736
Loans, past due	20	10
Loans	18,144	18,746
Consumer Portfolio Segment [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member]
Loans, past due	14	10
Consumer Portfolio Segment [Member] \| Financing Receivables, 60 to 89 Days Past Due [Member]
Loans, past due	6	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
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-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5074-111524

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