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Note 6 - Investment Securities Available for Sale (Details) - Amortized Cost and Fair Values of Securities Available for Sale - USD ($) $ in Thousands | Jun. 30, 2015 | Dec. 31, 2014
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Note 6 - Investment Securities Available for Sale (Details) - Amortized Cost and Fair Values of Securities Available for Sale [Line Items] |  |
Amortized Cost | $ 155,903 | $ 150,476
Gross Unrealized Gains | 3,774 | 5,095
Gross Unrealized Losses | (2,100) | (1,237)
Investment securities available for sale, at fair value | 157,577 | 154,334
US Government Agencies Debt Securities [Member] |  |
Note 6 - Investment Securities Available for Sale (Details) - Amortized Cost and Fair Values of Securities Available for Sale [Line Items] |  |
Amortized Cost | 22,404 | 23,035
Gross Unrealized Gains | 275 | 311
Gross Unrealized Losses | (457) | (450)
Investment securities available for sale, at fair value | 22,222 | 22,896
US States and Political Subdivisions Debt Securities [Member] | Taxable [Member] |  |
Note 6 - Investment Securities Available for Sale (Details) - Amortized Cost and Fair Values of Securities Available for Sale [Line Items] |  |
Amortized Cost | 1,991 | 2,953
Gross Unrealized Gains | 129 | 226
Investment securities available for sale, at fair value | 2,120 | 3,179
US States and Political Subdivisions Debt Securities [Member] | Tax-exempt [Member] |  |
Note 6 - Investment Securities Available for Sale (Details) - Amortized Cost and Fair Values of Securities Available for Sale [Line Items] |  |
Amortized Cost | 101,595 | 91,916
Gross Unrealized Gains | 2,652 | 3,803
Gross Unrealized Losses | (1,308) | (553)
Investment securities available for sale, at fair value | 102,939 | 95,166
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] |  |
Note 6 - Investment Securities Available for Sale (Details) - Amortized Cost and Fair Values of Securities Available for Sale [Line Items] |  |
Amortized Cost | 26,663 | 29,150
Gross Unrealized Gains | 354 | 475
Gross Unrealized Losses | (335) | (234)
Investment securities available for sale, at fair value | 26,682 | 29,391
Mortgage-backed Securities, Issued by Private Enterprises [Member] |  |
Note 6 - Investment Securities Available for Sale (Details) - Amortized Cost and Fair Values of Securities Available for Sale [Line Items] |  |
Amortized Cost | 2,500 | 2,672
Gross Unrealized Gains | 215 | 247
Investment securities available for sale, at fair value | 2,715 | 2,919
Debt Securities [Member] |  |
Note 6 - Investment Securities Available for Sale (Details) - Amortized Cost and Fair Values of Securities Available for Sale [Line Items] |  |
Amortized Cost | 155,153 | 149,726
Gross Unrealized Gains | 3,625 | 5,062
Gross Unrealized Losses | (2,100) | (1,237)
Investment securities available for sale, at fair value | 156,678 | 153,551
Equity Securities in Financial Institutions [Member] |  |
Note 6 - Investment Securities Available for Sale (Details) - Amortized Cost and Fair Values of Securities Available for Sale [Line Items] |  |
Amortized Cost | 750 | 750
Gross Unrealized Gains | 149 | 33
Investment securities available for sale, at fair value | $ 899 | $ 783

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- 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=51813488&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=27724398&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=49167202&loc=d3e26610-111562 + Details
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- Definition 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=27724398&loc=d3e27161-111563 + Details
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