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Note 4 - Securities - Securities Available-for-sale (Details) - USD ($) $ in Thousands | Mar. 31, 2017 | Dec. 31, 2016
--- | --- | ---
Securities available-for-sale, Amortized Costs | $ 308,241 | $ 309,842
Securities available-for-sale, Gross Unrealized Gains | 920 | 808
Securities available-for-sale, Gross Unrealized Losses | 4,785 | 6,328
Securities available-for-sale, Fair Values | 304,376 | 304,282
US Government Agencies Debt Securities [Member] |  |
Securities available-for-sale, Amortized Costs | 291,278 | 291,271
Securities available-for-sale, Gross Unrealized Gains | 584 | 492
Securities available-for-sale, Gross Unrealized Losses | 4,649 | 6,165
Securities available-for-sale, Fair Values | 287,213 | 285,598
US States and Political Subdivisions Debt Securities [Member] |  |
Securities available-for-sale, Amortized Costs | 9,977 | 11,482
Securities available-for-sale, Gross Unrealized Gains | 185 | 211
Securities available-for-sale, Gross Unrealized Losses | 0 | 0
Securities available-for-sale, Fair Values | 10,162 | 11,693
Collateralized Mortgage Backed Securities [Member] |  |
Securities available-for-sale, Amortized Costs | 782 | 845
Securities available-for-sale, Gross Unrealized Gains | 82 | 85
Securities available-for-sale, Gross Unrealized Losses | 0 | 0
Securities available-for-sale, Fair Values | 864 | 930
Corporate Debt Securities [Member] |  |
Securities available-for-sale, Amortized Costs | 6,015 | 6,015
Securities available-for-sale, Gross Unrealized Gains | 69 | 20
Securities available-for-sale, Gross Unrealized Losses | 127 | 137
Securities available-for-sale, Fair Values | 5,957 | 5,898
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 | 9 | 26
Securities available-for-sale, Fair Values | $ 180 | $ 163

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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=75030427&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=82897076&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=82896770&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=82897076&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=82897076&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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