Note 2 - Investment Securities (Details) - Investment Securities - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, amortized cost	$ 28,927	$ 29,625
Available-for-sale securities, gross unrealized losses	(192)	(319)
Available-for-sale securities, gross unrealized gains	0	71
Available-for-sale securities	28,735	29,377
US Government Agencies Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, amortized cost	5,000	5,000
Available-for-sale securities, gross unrealized losses	(11)	(46)
Available-for-sale securities, gross unrealized gains	0	0
Available-for-sale securities	4,989	4,954
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, amortized cost	12,927	13,625
Available-for-sale securities, gross unrealized losses	(78)	(212)
Available-for-sale securities, gross unrealized gains	0	0
Available-for-sale securities	12,849	13,413
Corporate Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, amortized cost	9,000	9,000
Available-for-sale securities, gross unrealized losses	(103)	(61)
Available-for-sale securities, gross unrealized gains	0	71
Available-for-sale securities	8,897	9,010
Subordinated Notes [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, amortized cost	2,000	2,000
Available-for-sale securities, gross unrealized losses	0	0
Available-for-sale securities, gross unrealized gains	0	0
Available-for-sale securities	$ 2,000	$ 2,000

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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