Note 2 - Investment Securities (Details Textual) $ in Thousands	6 Months Ended
Jun. 30, 2016 USD ($)	Jun. 30, 2015 USD ($)	Dec. 31, 2015 USD ($)
Corporate Debt Securities [Member]
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	0
US Government Agencies Debt Securities [Member]
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	10
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	$ 4,491		$ 6,923
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	8
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	$ 1,983		13,395
US States and Political Subdivisions Debt Securities [Member]
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	4
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	$ 1,133		1,331
Debt Securities [Member]
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	22
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	$ 7,600
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	7,607		$ 21,649
Available-for-sale Securities, Gross Realized Gains	219	$ 55
Available-for-sale Securities, Gross Realized Losses	$ 5	$ 15

This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27290-111563

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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

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 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

Number of investment positions in available-for-sale investments in a continuous unrealized loss position for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (b)(3)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27290-111563

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