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Note 6 - Amortized Cost and Fair Values of Securities Available for Sale (Details) - USD ($) $ in Thousands | Jun. 30, 2016 | Dec. 31, 2015
--- | --- | ---
US Government Agencies Debt Securities [Member] |  |
Amortized cost | $ 14,967 | $ 21,655
Gross unrealized gains | 378 | 245
Gross unrealized losses | (10) | (271)
Investment securities available for sale, at fair value | 15,335 | 21,629
US States and Political Subdivisions Debt Securities [Member] | Taxable [Member] |  |
Amortized cost | 1,618 | 1,989
Gross unrealized gains | 186 | 134
Gross unrealized losses |  |
Investment securities available for sale, at fair value | 1,804 | 2,123
US States and Political Subdivisions Debt Securities [Member] | Tax Exempt [Member] |  |
Amortized cost | 81,895 | 91,940
Gross unrealized gains | 4,656 | 3,402
Gross unrealized losses |  | (175)
Investment securities available for sale, at fair value | 86,551 | 95,167
US States and Political Subdivisions Debt Securities [Member] |  |
Investment securities available for sale, at fair value | 88,355 | 97,290
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] |  |
Amortized cost | 22,261 | 24,480
Gross unrealized gains | 508 | 316
Gross unrealized losses | (50) | (272)
Investment securities available for sale, at fair value | 22,719 | 24,524
Mortgage-backed Securities, Issued by Private Enterprises [Member] |  |
Amortized cost | 1,927 | 2,079
Gross unrealized gains | 146 | 184
Gross unrealized losses | (1) |
Investment securities available for sale, at fair value | 2,072 | 2,263
Debt Securities [Member] |  |
Amortized cost | 122,668 | 142,143
Gross unrealized gains | 5,874 | 4,281
Gross unrealized losses | (61) | (718)
Investment securities available for sale, at fair value | 128,481 | 145,706
Equity Securities In Financial Institutions [Member] |  |
Amortized cost | 750 | 750
Gross unrealized gains | 64 | 64
Gross unrealized losses |  |
Investment securities available for sale, at fair value | 814 | 814
Amortized cost | 123,418 | 142,893
Gross unrealized gains | 5,938 | 4,345
Gross unrealized losses | (61) | (718)
Investment securities available for sale, at fair value | $ 129,295 | $ 146,520

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=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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X
- 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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- Definition Amount before tax of unrealized loss 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 (c) -URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27161-111563 + Details
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- Definition This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.2) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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