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Note 4 - Fair Value Disclosure Measurments - Assets Measured on a Recurring Basis (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Investment securities available for sale, at fair value	$ 104,951	$ 114,376
US Government Agencies Debt Securities [Member]
Investment securities available for sale, at fair value	9,514	10,236
US States and Political Subdivisions Debt Securities [Member]
Investment securities available for sale, at fair value	77,635	81,223
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Investment securities available for sale, at fair value	17,512	20,069
Debt Securities [Member]
Investment securities available for sale, at fair value	104,661	113,237
Mortgage-backed Securities, Issued by Private Enterprises [Member]
Investment securities available for sale, at fair value		1,709
Equity Securities In Financial Institutions [Member]
Investment securities available for sale, at fair value	290	1,139
Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring [Member]
Investment securities available for sale, at fair value	104,951	114,376
Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring [Member] | US Government Agencies Debt Securities [Member]
Investment securities available for sale, at fair value	9,514	10,236
Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring [Member] | US States and Political Subdivisions Debt Securities [Member]
Investment securities available for sale, at fair value	77,635	81,223
Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring [Member] | Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Investment securities available for sale, at fair value	17,512	20,069
Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring [Member] | Debt Securities [Member]
Investment securities available for sale, at fair value	104,661	113,237
Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring [Member] | Mortgage-backed Securities, Issued by Private Enterprises [Member]
Investment securities available for sale, at fair value		1,709
Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring [Member] | Equity Securities In Financial Institutions [Member]
Investment securities available for sale, at fair value	$ 290	$ 1,139

X

- Definition

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

+ References

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
-Paragraph 5
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=82897076&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=82896770&loc=d3e26610-111562

+ Details

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