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Note 3 - Investment Securities Available for Sale (Details) - Amortized Cost and Fair Values of Securities Available for Sale - USD ($) $ in Thousands | Dec. 31, 2015 | Dec. 31, 2014
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Note 3 - Investment Securities Available for Sale (Details) - Amortized Cost and Fair Values of Securities Available for Sale [Line Items] |  |
Amortized cost | $ 142,893 | $ 150,476
Gross unrealized gains | 4,345 | 5,095
Gross unrealized losses | (718) | (1,237)
Investment securities available for sale, at fair value | 146,520 | 154,334
US Government Agencies Debt Securities [Member] |  |
Note 3 - Investment Securities Available for Sale (Details) - Amortized Cost and Fair Values of Securities Available for Sale [Line Items] |  |
Amortized cost | 21,655 | 23,035
Gross unrealized gains | 245 | 311
Gross unrealized losses | (271) | (450)
Investment securities available for sale, at fair value | 21,629 | 22,896
US States and Political Subdivisions Debt Securities [Member] | Taxable [Member] |  |
Note 3 - Investment Securities Available for Sale (Details) - Amortized Cost and Fair Values of Securities Available for Sale [Line Items] |  |
Amortized cost | 1,989 | 2,953
Gross unrealized gains | 134 | 226
Gross unrealized losses | 0 | 0
Investment securities available for sale, at fair value | 2,123 | 3,179
US States and Political Subdivisions Debt Securities [Member] | Tax-exempt [Member] |  |
Note 3 - Investment Securities Available for Sale (Details) - Amortized Cost and Fair Values of Securities Available for Sale [Line Items] |  |
Amortized cost | 91,940 | 91,916
Gross unrealized gains | 3,402 | 3,803
Gross unrealized losses | (175) | (553)
Investment securities available for sale, at fair value | 95,167 | 95,166
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] |  |
Note 3 - Investment Securities Available for Sale (Details) - Amortized Cost and Fair Values of Securities Available for Sale [Line Items] |  |
Amortized cost | 24,480 | 29,150
Gross unrealized gains | 316 | 475
Gross unrealized losses | (272) | (234)
Investment securities available for sale, at fair value | 24,524 | 29,391
Mortgage-backed Securities, Issued by Private Enterprises [Member] |  |
Note 3 - Investment Securities Available for Sale (Details) - Amortized Cost and Fair Values of Securities Available for Sale [Line Items] |  |
Amortized cost | 2,079 | 2,672
Gross unrealized gains | 184 | 247
Gross unrealized losses | 0 | 0
Investment securities available for sale, at fair value | 2,263 | 2,919
Debt Securities [Member] |  |
Note 3 - Investment Securities Available for Sale (Details) - Amortized Cost and Fair Values of Securities Available for Sale [Line Items] |  |
Amortized cost | 142,143 | 149,726
Gross unrealized gains | 4,281 | 5,062
Gross unrealized losses | (718) | (1,237)
Investment securities available for sale, at fair value | 145,706 | 153,551
Equity Securities in Financial Institutions [Member] |  |
Note 3 - 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 | 33
Gross unrealized losses | 0 | 0
Investment securities available for sale, at fair value | $ 814 | $ 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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