Note 3 - Securities Held-to-Maturity (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
US States and Political Subdivisions Debt Securities [Member]
Amortized cost	$ 19,305	$ 19,898
Gross unrecognized gains	1,181	892
Gross unrecognized losses		(5)
Estimated fair value	20,486	20,785
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Amortized cost	5	5
Gross unrecognized gains
Gross unrecognized losses
Estimated fair value	5	5
Amortized cost	19,310	19,903
Gross unrecognized gains	1,181	892
Gross unrecognized losses		(5)
Estimated fair value	$ 20,491	$ 20,790

Amount of accumulated unrealized gain on investments in debt securities classified as held-to-maturity.

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- Definition

Amount of accumulated unrealized loss on investments in debt securities classified as held-to-maturity.

+ References

+ Details

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- Definition

Amount before other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

+ References

No definition available.

+ Details

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- Definition

Fair value of investments in debt securities classified as held-to-maturity.

+ References

Reference 1: 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 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (f)
-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 50
-Paragraph 5
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27232-111563

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