Note 4 - Loans and Related Allowance for Loan Losses (Details) - Past Due Financing Receivables (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans, current balance	$ 465,164	$ 426,466
Loans, 30-59 days past due	2,471	4,316
Loans, 60-89 days past due	434	1,598
Loans, 90+ days past due	2,515	3,345
Loans, total past due	5,420	9,259
Loans, total	470,584	435,725
Commercial and Industrial [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans, current balance	60,296	53,440
Loans, 30-59 days past due	349	529
Loans, 60-89 days past due	68	359
Loans, 90+ days past due	31	170
Loans, total past due	448	1,058
Loans, total	60,744	54,498
Real Estate Construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans, current balance	30,296	24,945
Loans, 30-59 days past due		17
Loans, 60-89 days past due		639
Loans, total past due		656
Loans, total	30,296	25,601
Residential Real Estate Mortgage [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans, current balance	223,209	203,747
Loans, 30-59 days past due	2,065	3,082
Loans, 60-89 days past due	363	481
Loans, 90+ days past due	1,915	3,000
Loans, total past due	4,343	6,563
Loans, total	227,552	210,310
Commercial Real Estate Mortgage [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans, current balance	146,816	140,251
Loans, 30-59 days past due	30	645
Loans, 60-89 days past due		100
Loans, 90+ days past due	567	175
Loans, total past due	597	920
Loans, total	147,413	141,171
Consumer Installment [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans, current balance	4,547	4,083
Loans, 30-59 days past due	27	43
Loans, 60-89 days past due	3	19
Loans, 90+ days past due	2
Loans, total past due	32	62
Loans, total	$ 4,579	$ 4,145

Financing receivables that are less than 60 days past due but more than 29 days past due.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 7A

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953401-111524

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- Definition

Financing receivables that are less than 90 days past due but more than 59 days past due.

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- Definition

Financing receivables that are current.

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Financing receivables that are equal to or greater than 90 days past due.

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

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- Definition

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://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5074-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522

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