Note 8 - Loans (Details) - Average Balance and Interest Income Recognized Related to Impaired Loans - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Financing Receivable, Impaired [Line Items]
Loans, average recorded investment	$ 160,349	$ 190,744	$ 168,472	$ 192,752
Loans, interest income recognized	1,152	1,552	3,221	4,507
Commercial Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Loans, average recorded investment	23,894	21,706	24,974	26,741
Loans, interest income recognized	170	205	519	636
Real Estate Construction Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Loans, average recorded investment	22,392	33,276	22,056	33,459
Loans, interest income recognized	66	66	196	198
Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Loans, average recorded investment	97,557	119,611	104,508	114,663
Loans, interest income recognized	777	1,153	2,126	3,310
Residential Mortgage and Equity Lines Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Loans, average recorded investment	16,506	16,151	16,934	17,889
Loans, interest income recognized	$ 139	$ 128	$ 380	$ 363

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.

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