Note 7 - Loans (Details) - Impaired Loans and Related Allowance for Credit Losses (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
With no allocated allowance
Loans with no related allowance, unpaid principal balance	$ 159,216	$ 132,395
Loans with no related allowance, recorded investment	123,660	113,167
With allocated allowance
Loans with related allowance, unpaid principal balance	58,599	78,225
Loans with related allowance, recorded investment	57,057	61,352
Allowance	11,044	11,798
Total impaired loans	217,815	210,620
Total impaired loans	180,717	174,519
Total impaired loans	11,044	11,798
Commercial Loans [Member]
With allocated allowance
Loans with related allowance, unpaid principal balance	15,677	7,003
Loans with related allowance, recorded investment	15,660	5,037
Allowance	3,911	1,263
Total impaired loans	3,911	1,263
Real Estate Construction Loans [Member]
With allocated allowance
Loans with related allowance, unpaid principal balance		19,006
Loans with related allowance, recorded investment		8,703
Allowance		1,077
Total impaired loans		1,077
Commercial Mortgage Loans [Member]
With allocated allowance
Loans with related allowance, unpaid principal balance	27,529	38,197
Loans with related allowance, recorded investment	26,581	34,022
Allowance	6,635	8,993
Total impaired loans	6,635	8,993
Residential Mortgage and Equity Lines [Member]
With allocated allowance
Loans with related allowance, unpaid principal balance	15,393	14,019
Loans with related allowance, recorded investment	14,816	13,590
Allowance	498	465
Total impaired loans	498	465
Commercial Loans [Member]
With no allocated allowance
Loans with no related allowance, unpaid principal balance	14,176	19,479
Loans with no related allowance, recorded investment	13,148	18,452
Real Estate Construction Loans [Member]
With no allocated allowance
Loans with no related allowance, unpaid principal balance	49,076	32,924
Loans with no related allowance, recorded investment	22,874	17,025
Commercial Mortgage Loans [Member]
With no allocated allowance
Loans with no related allowance, unpaid principal balance	93,468	77,474
Loans with no related allowance, recorded investment	85,142	75,172
Residential Mortgage and Equity Lines [Member]
With no allocated allowance
Loans with no related allowance, unpaid principal balance	2,496	2,518
Loans with no related allowance, recorded investment	$ 2,496	$ 2,518

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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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+ 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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-Publisher FASB

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+ References

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-Publisher FASB

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-Section 50

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-Subparagraph (a)(4)

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

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