Note 4 - Investment Securities Available for Sale (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
US Treasury and Government [Member]
Available-for-sale Securities, Amortized Cost Basis	$ 46,605	$ 49,612
Available for sale securities, gross unrealized gains	20	5
Available for sale securities, gross unrealized losses	(18)	(117)
Available-for-sale Securities	46,607	49,500
US States and Political Subdivisions Debt Securities [Member]
Available-for-sale Securities, Amortized Cost Basis	62,058	63,276
Available for sale securities, gross unrealized gains	854	717
Available for sale securities, gross unrealized losses	(50)	(60)
Available-for-sale Securities	62,862	63,933
Collateralized Mortgage Backed Securities [Member]
Available-for-sale Securities, Amortized Cost Basis	74,813	85,072
Available for sale securities, gross unrealized gains	899	647
Available for sale securities, gross unrealized losses	(38)	(567)
Available-for-sale Securities	75,674	85,152
Available-for-sale Securities, Amortized Cost Basis	183,476	197,960
Available for sale securities, gross unrealized gains	1,773	1,369
Available for sale securities, gross unrealized losses	(106)	(744)
Available-for-sale Securities	$ 185,143	$ 198,585

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=65884222&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27232-111563

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=66010992&loc=d3e26610-111562

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- Definition

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27161-111563

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- Definition

Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27161-111563

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- Definition

This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.2)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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