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Note 3 - Securities - Securities Available-for-sale (Details) - USD ($) $ in Thousands | Dec. 31, 2016 | Dec. 31, 2015
--- | --- | ---
Securities available-for-sale, Amortized Costs | $ 309,802 | $ 240,234
Securities available-for-sale, Gross Unrealized Gains | 808 | 1,202
Securities available-for-sale, Gross Unrealized Losses | 6,328 | 5,305
Securities available-for-sale, Fair Values | 304,282 | 236,131
US Government Agencies Debt Securities [Member] |  |
Securities available-for-sale, Amortized Costs | 291,271 | 216,897
Securities available-for-sale, Gross Unrealized Gains | 492 | 519
Securities available-for-sale, Gross Unrealized Losses | 6,165 | 4,952
Securities available-for-sale, Fair Values | 285,598 | 212,464
US States and Political Subdivisions Debt Securities [Member] |  |
Securities available-for-sale, Amortized Costs | 11,482 | 15,934
Securities available-for-sale, Gross Unrealized Gains | 211 | 541
Securities available-for-sale, Gross Unrealized Losses | 0 | 0
Securities available-for-sale, Fair Values | 11,693 | 16,475
Collateralized Mortgage Backed Securities [Member] |  |
Securities available-for-sale, Amortized Costs | 845 | 1,199
Securities available-for-sale, Gross Unrealized Gains | 85 | 120
Securities available-for-sale, Gross Unrealized Losses | 0 | 0
Securities available-for-sale, Fair Values | 930 | 1,319
Corporate Debt Securities [Member] |  |
Securities available-for-sale, Amortized Costs | 6,015 | 6,015
Securities available-for-sale, Gross Unrealized Gains | 20 | 22
Securities available-for-sale, Gross Unrealized Losses | 137 | 291
Securities available-for-sale, Fair Values | 5,898 | 5,746
Other Securities [Member] |  |
Securities available-for-sale, Amortized Costs | 189 | 189
Securities available-for-sale, Gross Unrealized Gains | 0 | 0
Securities available-for-sale, Gross Unrealized Losses | 26 | 62
Securities available-for-sale, Fair Values | $ 163 | $ 127

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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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- 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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