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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 | Sep. 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 | $ 142,243 | $ 150,476
Gross unrealized gains | 3,971 | 5,095
Gross unrealized losses | (1,068) | (1,237)
Investment securities available for sale, at fair value | 145,146 | 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 | 21,984 | 23,035
Gross unrealized gains | 298 | 311
Gross unrealized losses | (264) | (450)
Investment securities available for sale, at fair value | 22,018 | 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 | 1,990 | 2,953
Gross unrealized gains | 156 | 226
Investment securities available for sale, at fair value | 2,146 | 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 | 89,932 | 91,916
Gross unrealized gains | 2,759 | 3,803
Gross unrealized losses | (664) | (553)
Investment securities available for sale, at fair value | 92,027 | 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 | 25,400 | 29,150
Gross unrealized gains | 409 | 475
Gross unrealized losses | (140) | (234)
Investment securities available for sale, at fair value | 25,669 | 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 | 2,187 | 2,672
Gross unrealized gains | 200 | 247
Investment securities available for sale, at fair value | 2,387 | 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 | 141,493 | 149,726
Gross unrealized gains | 3,822 | 5,062
Gross unrealized losses | (1,068) | (1,237)
Investment securities available for sale, at fair value | 144,247 | 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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