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Note 3 - Securities (Details) - Available-for-sale Securities - USD ($) | Dec. 31, 2015 | Dec. 31, 2014
--- | --- | ---
2015 |  |
Available-for-sale Securities, Amortized Cost | $ 344,796,000 | $ 432,591,000
Available-for-sale Securities, Gross Unrealized Gains | 4,265,000 | 3,897,000
Available-for-sale Securities, Gross Unrealized Losses | (2,069,000) | (3,576,000)
Securities available for sale | 346,992,000 | 432,912,000
US Government Agencies Debt Securities [Member] |  |
2015 |  |
Available-for-sale Securities, Amortized Cost | 146,660,000 | 194,894,000
Available-for-sale Securities, Gross Unrealized Gains | 1,932,000 | 1,612,000
Available-for-sale Securities, Gross Unrealized Losses | (1,552,000) | (3,038,000)
Securities available for sale | 147,040,000 | 193,468,000
Collateralized Mortgage Backed Securities [Member] |  |
2015 |  |
Available-for-sale Securities, Amortized Cost | 66,670,000 | 92,656,000
Available-for-sale Securities, Gross Unrealized Gains | 708,000 | 1,123,000
Available-for-sale Securities, Gross Unrealized Losses | (304,000) | (218,000)
Securities available for sale | 67,074,000 | 93,561,000
Municipal General Obligation Bonds [Member] |  |
2015 |  |
Available-for-sale Securities, Amortized Cost | 120,679,000 | 132,347,000
Available-for-sale Securities, Gross Unrealized Gains | 1,549,000 | 1,042,000
Available-for-sale Securities, Gross Unrealized Losses | (205,000) | (307,000)
Securities available for sale | 122,023,000 | 133,082,000
Municipal Revenue Bonds [Member] |  |
2015 |  |
Available-for-sale Securities, Amortized Cost | 8,841,000 | 10,769,000
Available-for-sale Securities, Gross Unrealized Gains | 76,000 | 117,000
Available-for-sale Securities, Gross Unrealized Losses | (3,000) | (13,000)
Securities available for sale | 8,914,000 | 10,873,000
Other Debt Obligations [Member] |  |
2015 |  |
Available-for-sale Securities, Amortized Cost | 1,946,000 | 1,925,000
Available-for-sale Securities, Gross Unrealized Gains | 0 | 3,000
Available-for-sale Securities, Gross Unrealized Losses | (5,000) | 0
Securities available for sale | $ 1,941,000 | $ 1,928,000

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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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- 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=27724398&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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