Note 4 - Loans and Allowance for Credit Losses (Details) - Impaired Loans (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Commercial [Member]
Impaired loans with no related allowance recorded:
Impaired loans with no related allowance recorded, recorded investment	$ 3,389	$ 3,931
Impaired loans with no related allowance recorded, unpaid principal balance	3,563	4,498
Impaired loans with an allowance recorded:
Impaired loans with an allowance recorded, recorded investment	259	1,000
Impaired loans with an allowance recorded, unpaid principal balance	259	2,173
Impaired loans with an allowance recorded, related allowance	259	100
Total:
Recorded Investment	3,648	4,931
Unpaid Principal Balance	3,822	6,671
Related Allowance	259	100
Commercial Real Estate Loans [Member]
Impaired loans with no related allowance recorded:
Impaired loans with no related allowance recorded, recorded investment	13,463	11,002
Impaired loans with no related allowance recorded, unpaid principal balance	16,044	13,253
Impaired loans with an allowance recorded:
Impaired loans with an allowance recorded, recorded investment	6,330	9,773
Impaired loans with an allowance recorded, unpaid principal balance	9,796	12,482
Impaired loans with an allowance recorded, related allowance	633	1,396
Total:
Recorded Investment	19,793	20,775
Unpaid Principal Balance	25,840	25,735
Related Allowance	633	1,396
Construction [Member]
Impaired loans with no related allowance recorded:
Impaired loans with no related allowance recorded, recorded investment	1,834	2,483
Impaired loans with no related allowance recorded, unpaid principal balance	1,884	2,947
Total:
Recorded Investment	1,834	2,483
Unpaid Principal Balance	1,884	2,947
Consumer Installment And Other [Member]
Impaired loans with no related allowance recorded:
Impaired loans with no related allowance recorded, recorded investment	1,183	2,014
Impaired loans with no related allowance recorded, unpaid principal balance	1,332	2,133
Total:
Recorded Investment	1,183	2,014
Unpaid Principal Balance	$ 1,332	$ 2,133

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

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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+ 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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+ 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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+ 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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+ 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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