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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 | Mar. 31, 2016 | Dec. 31, 2015
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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 | $ 138,437 | $ 142,893
Gross unrealized gains | 4,491 | 4,345
Gross unrealized losses | (368) | (718)
Investment securities available for sale, at fair value | 142,560 | 146,520
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 | 18,616 | 21,655
Gross unrealized gains | 313 | 245
Gross unrealized losses | (76) | (271)
Investment securities available for sale, at fair value | 18,853 | 21,629
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 | 23,550 | 24,480
Gross unrealized gains | 380 | 316
Gross unrealized losses | (117) | (272)
Investment securities available for sale, at fair value | 23,813 | 24,524
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 | 1,927 | 2,079
Gross unrealized gains | 153 | 184
Gross unrealized losses | (1) | 0
Investment securities available for sale, at fair value | 2,079 | 2,263
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 | 137,687 | 142,143
Gross unrealized gains | 4,427 | 4,281
Gross unrealized losses | (368) | (718)
Investment securities available for sale, at fair value | 141,746 | 145,706
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 | 64 | 64
Gross unrealized losses | 0 | 0
Investment securities available for sale, at fair value | 814 | 814
Taxable [Member] | US States and Political Subdivisions 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 | 1,989 | 1,989
Gross unrealized gains | 187 | 134
Gross unrealized losses | (1) | 0
Investment securities available for sale, at fair value | 2,175 | 2,123
Tax-exempt [Member] | US States and Political Subdivisions 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 | 91,605 | 91,940
Gross unrealized gains | 3,394 | 3,402
Gross unrealized losses | (173) | (175)
Investment securities available for sale, at fair value | $ 94,826 | $ 95,167

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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=65884222&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=73527792&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=66010992&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=73527792&loc=d3e27161-111563 + Details
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