Note 4 - Securities (Details) - Sales of Securities (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Note 4 - Securities (Details) - Sales of Securities [Line Items]
Proceeds from sales of securities	$ 93,545	$ 103,303	$ 112,149
Gross realized gains on sales of securities:
Gross realized gains on sales of securities	796	1,585	4,006
Gross realized losses on sales of securities	(955)	(590)	(184)
US Government Agencies Debt Securities [Member]
Gross realized gains on sales of securities:
Gross realized gains on sales of securities	32
Gross realized losses on sales of securities	(114)	(100)
Obligations of State and Political Subdivisions [Member]
Gross realized gains on sales of securities:
Gross realized gains on sales of securities	268	261	2,710
Gross realized losses on sales of securities	(209)	(215)
Residential Mortgage Backed Securities and Collateralized Mortgage Obligations [Member]
Gross realized gains on sales of securities:
Gross realized gains on sales of securities	102	250	594
Gross realized losses on sales of securities	(570)	(199)	(158)
Corporate Debt Securities [Member]
Gross realized gains on sales of securities:
Gross realized gains on sales of securities	317	1,022	464
Gross realized losses on sales of securities	(8)	(29)	(16)
Commercial Mortgage Backed Securities [Member]
Gross realized gains on sales of securities:
Gross realized gains on sales of securities	4		43
Gross realized losses on sales of securities	(32)		(10)
Asset-backed Securities [Member]
Gross realized gains on sales of securities:
Gross realized gains on sales of securities	73	52	195
Gross realized losses on sales of securities	$ (22)	$ (47)

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This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 9

-Subparagraph (a)

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The cash inflow associated with the sale of debt and equity securities classified as available-for-sale securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 45

-Paragraph 11

-URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26853-111562

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 12

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