Note 5 - Securities (Details) - Sales of Securities (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Note 5 - Securities (Details) - Sales of Securities [Line Items]
Proceeds from sales of securities	$ 25,215	$ 36,686
Gross realized gains on sales of securities:
Gross realized gains on sales of securities	224	327
Gross realized losses on sales of securities:
Gross realized losses on sales of securities	(9)	(572)
Gain (loss) on investment securities, net	215	(245)
US Government Agencies Debt Securities [Member]
Gross realized gains on sales of securities:
Gross realized gains on sales of securities	32
Obligations of State and Political Subdivisions [Member]
Gross realized gains on sales of securities:
Gross realized gains on sales of securities	13	157
Gross realized losses on sales of securities:
Gross realized losses on sales of securities		(90)
Residential Mortgage Backed Securities and Collateralized Mortgage Obligations [Member]
Gross realized gains on sales of securities:
Gross realized gains on sales of securities	82	6
Gross realized losses on sales of securities:
Gross realized losses on sales of securities	(9)	(469)
Corporate Debt Securities [Member]
Gross realized gains on sales of securities:
Gross realized gains on sales of securities	4	141
Commercial Mortgage Backed Securities [Member]
Gross realized gains on sales of securities:
Gross realized gains on sales of securities	93
Gross realized losses on sales of securities:
Gross realized losses on sales of securities		(1)
Asset-backed Securities [Member]
Gross realized gains on sales of securities:
Gross realized gains on sales of securities		23
Gross realized losses on sales of securities:
Gross realized losses on sales of securities		$ (12)

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This item represents the difference between the gross realized gains and losses realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. Additionally, this item would include any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt and equity 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)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27357-111563

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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

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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

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 12

-Subparagraph (a),(b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3179-108585

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