Note 7 - Loans (Details) - Average Balance and Interest Income Recognized Related to Impaired Loans - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Financing Receivable, Impaired [Line Items]
Loans, average recorded investment	$ 169,250	$ 192,196	$ 172,601	$ 193,772
Loans, interest income recognized	1,179	1,348	2,356	2,758
Commercial Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Loans, average recorded investment	25,620	27,773	25,523	29,300
Loans, interest income recognized	201	194	412	420
Real Estate Construction Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Loans, average recorded investment	20,790	33,049	21,884	33,552
Loans, interest income recognized	65	66	130	132
Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Loans, average recorded investment	105,815	112,982	108,042	112,148
Loans, interest income recognized	793	995	1,574	2,014
Residential Mortgage and Equity Lines Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Loans, average recorded investment	17,025	18,392	17,152	18,772
Loans, interest income recognized	$ 120	$ 93	$ 240	$ 192

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Average 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 15

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5212-111524

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 17

-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5258-111524

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Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

+ References

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