Note 2 - Investment Securities - Available-for-sale Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
US Government Agencies Debt Securities [Member]
Securities available-for-sale, amortized cost	$ 13,598	$ 16,899
Securities available-for-sale, gross unrealized gains	300	227
Securities available-for-sale, gross unrealized losses	(40)	(107)
Securities available-for-sale	13,858	17,019
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Securities available-for-sale, amortized cost	21,395	18,289
Securities available-for-sale, gross unrealized gains	211	75
Securities available-for-sale, gross unrealized losses	(28)	(174)
Securities available-for-sale	21,578	18,190
Corporate Debt Securities [Member]
Securities available-for-sale, amortized cost	2,500
Securities available-for-sale, gross unrealized gains
Securities available-for-sale, gross unrealized losses
Securities available-for-sale	2,500
US States and Political Subdivisions Debt Securities [Member]
Securities available-for-sale, amortized cost	15,887	16,756
Securities available-for-sale, gross unrealized gains	686	594
Securities available-for-sale, gross unrealized losses	(11)	(15)
Securities available-for-sale	16,562	17,335
Securities available-for-sale, amortized cost	53,380	51,944
Securities available-for-sale, gross unrealized gains	1,197	896
Securities available-for-sale, gross unrealized losses	(79)	(296)
Securities available-for-sale	$ 54,498	$ 52,544

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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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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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
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-Paragraph 2
-Subparagraph (c)
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+ 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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