Note 7 - Loans and Related Allowance for Loan and Lease Losses (Details) - Impaired Loans by Class (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
With no related allowance recorded:
Recorded investment, with no related allowance	$ 7,909	$ 10,119
Unpaid principal balance, with no related allowance	7,891	10,107
With an allowance recorded:
Recorded investment, with related allowance	4,148	4,249
Unpaid principal balance, with related allowance	4,142	4,246
Related allowance	998	1,596
Total:
Recorded investment	12,057	14,368
Unpaid principal balance	12,033	14,353
Related allowance	998	1,596
Commercial and Industrial [Member]
With no related allowance recorded:
Recorded investment, with no related allowance	692	1,146
Unpaid principal balance, with no related allowance	691	1,145
With an allowance recorded:
Recorded investment, with related allowance	369	247
Unpaid principal balance, with related allowance	368	247
Related allowance	65	83
Total:
Recorded investment	1,061	1,393
Unpaid principal balance	1,059	1,392
Related allowance	65	83
Real Estate Construction [Member]
With no related allowance recorded:
Recorded investment, with no related allowance	2,286	2,707
Unpaid principal balance, with no related allowance	2,281	2,705
With an allowance recorded:
Recorded investment, with related allowance	181	589
Unpaid principal balance, with related allowance	181	589
Related allowance	181	589
Total:
Recorded investment	2,467	3,296
Unpaid principal balance	2,462	3,294
Related allowance	181	589
Residential Real Estate Mortgage [Member]
With no related allowance recorded:
Recorded investment, with no related allowance	1,857	2,202
Unpaid principal balance, with no related allowance	1,855	2,197
With an allowance recorded:
Recorded investment, with related allowance	2,625	2,981
Unpaid principal balance, with related allowance	2,622	2,978
Related allowance	550	892
Total:
Recorded investment	4,482	5,183
Unpaid principal balance	4,477	5,175
Related allowance	550	892
Commercial Real Estate Mortgage [Member]
With no related allowance recorded:
Recorded investment, with no related allowance	3,074	4,064
Unpaid principal balance, with no related allowance	3,064	4,060
With an allowance recorded:
Recorded investment, with related allowance	967	426
Unpaid principal balance, with related allowance	965	426
Related allowance	200	30
Total:
Recorded investment	4,041	4,490
Unpaid principal balance	4,029	4,486
Related allowance	200	30
Consumer Installment [Member]
With an allowance recorded:
Recorded investment, with related allowance	6	6
Unpaid principal balance, with related allowance	6	6
Related allowance	2	2
Total:
Recorded investment	6	6
Unpaid principal balance	6	6
Related allowance	$ 2	$ 2

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Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 14A

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953550-111524

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- Definition

Amount of allowance for credit losses related to recorded investment.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5212-111524

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Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without related allowance for credit losses.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (a)(4)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5212-111524

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Amount of investment in impaired financing receivables for which there is no related allowance for credit losses.

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Amount of unpaid principal balance of impaired financing receivables for which there is no related allowance for credit losses.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (a)(4)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5212-111524

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Unpaid principal balance of impaired financing receivables for which there is a related allowance for credit losses.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (a)(4)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5212-111524

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