Note 5 - Loans (Details) - Impaired Loans and Related Allowance for Credit Losses (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
With allocated allowance
Allowance	$ 11,798	$ 13,284
Total impaired loans	210,620	263,848
Total impaired loans	174,519	200,780
Total impaired loans	11,798	13,284
Commercial Loans [Member]
With no allocated allowance
Loans with no related allowance, unpaid principal balance	19,479	20,992
Loans with no related allowance, recorded investment	18,452	18,905
Real Estate Construction Loans [Member]
With no allocated allowance
Loans with no related allowance, unpaid principal balance	32,924	25,401
Loans with no related allowance, recorded investment	17,025	15,097
Commercial Mortgage Loans [Member]
With no allocated allowance
Loans with no related allowance, unpaid principal balance	77,474	105,593
Loans with no related allowance, recorded investment	75,172	78,930
Residential Mortgage And Equity Lines Member
With no allocated allowance
Loans with no related allowance, unpaid principal balance	2,518	4,892
Loans with no related allowance, recorded investment	2,518	4,892
With No Allocated Allowance Member
With no allocated allowance
Loans with no related allowance, unpaid principal balance	132,395	156,878
Loans with no related allowance, recorded investment	113,167	117,824
Commercial Loans [Member]
With allocated allowance
Loans with related allowance, unpaid principal balance	7,003	22,737
Loans with related allowance, recorded investment	5,037	13,063
Allowance	1,263	2,519
Total impaired loans	1,263	2,519
Real Estate Construction Loans [Member]
With allocated allowance
Loans with related allowance, unpaid principal balance	19,006	28,475
Loans with related allowance, recorded investment	8,703	19,323
Allowance	1,077	3,460
Total impaired loans	1,077	3,460
Commercial Mortgage Loans [Member]
With allocated allowance
Loans with related allowance, unpaid principal balance	38,197	39,223
Loans with related allowance, recorded investment	34,022	35,613
Allowance	8,993	6,584
Total impaired loans	8,993	6,584
Residential Mortgage And Equity Lines Member
With allocated allowance
Loans with related allowance, unpaid principal balance	14,019	16,535
Loans with related allowance, recorded investment	13,590	14,957
Allowance	465	721
Total impaired loans	465	721
With Allocated Allowance Member
With allocated allowance
Loans with related allowance, unpaid principal balance	78,225	106,970
Loans with related allowance, recorded investment	61,352	82,956
Allowance	11,798	13,284
Total impaired loans	$ 11,798	$ 13,284

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- Definition

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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Amount of allowance for credit losses related to recorded investment.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (a)(3)

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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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+ References

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-Publisher FASB

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-Topic 310

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-Section 50

-Paragraph 15

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

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