Note 7 - Loans (Details) - Average Balance and Interest Income Recognized Related to Impaired Loans - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Financing Receivable, Impaired [Line Items]
Loans, average recorded investment	$ 137,405	$ 175,989
Loans, interest income recognized	1,207	1,335
Commercial Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Loans, average recorded investment	12,670	25,426
Loans, interest income recognized	120	229
Real Estate Construction Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Loans, average recorded investment	20,292	22,990
Loans, interest income recognized	65	65
Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Loans, average recorded investment	87,452	110,293
Loans, interest income recognized	890	917
Residential Mortgage and Equity Lines Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Loans, average recorded investment	16,991	17,280
Loans, interest income recognized	$ 132	$ 124

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=66008989&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=66008989&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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