Note 4 - Securities - Sales of Securities (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
US States and Political Subdivisions Debt Securities [Member]
Gross realized gains on sales of securities	$ 40	$ 37	$ 111	$ 70
Residential Mortgage Backed Securities and Collateralized Mortgage Obligations [Member]
Gross realized gains on sales of securities	2	49	2	62
Gross realized losses on sales of securities	(64)		(64)	(9)
Corporate Debt Securities [Member]
Gross realized gains on sales of securities	33		76	82
Gross realized losses on sales of securities			(25)
Commercial Mortgage Backed Securities [Member]
Gross realized gains on sales of securities			5	4
Asset-backed Securities [Member]
Gross realized gains on sales of securities	21		21	93
Gross realized losses on sales of securities	(4)	(24)	(4)	(25)
US Government Agencies Debt Securities [Member]
Gross realized losses on sales of securities		(1)		(1)
Proceeds from sales of securities	14,455	10,697	34,389	35,912
Gross realized gains on sales of securities	96	86	215	311
Gross realized losses on sales of securities	(68)	(25)	(93)	(35)
Gain on investment securities, net	$ 28	$ 61	$ 122	$ 276

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.

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=73527792&loc=d3e27357-111563

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- Definition

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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- Definition

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

+ References

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- Definition

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=66010992&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=66902209&loc=d3e3179-108585

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