Note 3 - Securities - Securities Available-for-sale (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Securities available for sale, amortized cost	$ 103,979	$ 97,991
Securities available for sale, gross unrealized gains	607	495
Securities available for sale, gross unrealized losses	(1,414)	(1,996)
Securities available for sale	103,172	96,490
US Government-sponsored Enterprises Debt Securities [Member]
Securities available for sale, amortized cost	10,622	10,624
Securities available for sale, gross unrealized gains
Securities available for sale, gross unrealized losses	(46)	(80)
Securities available for sale	10,576	10,544
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Securities available for sale, amortized cost	93,357	87,367
Securities available for sale, gross unrealized gains	607	495
Securities available for sale, gross unrealized losses	(1,368)	(1,916)
Securities available for sale	$ 92,596	$ 85,946

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=75030427&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
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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
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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
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-Section 50
-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)
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