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Note 2 - Securities - Available-for-sale Securities (Details) - USD ($) | Sep. 30, 2016 | Dec. 31, 2015
--- | --- | ---
US Government Agencies Debt Securities [Member] |  |
Amortized Cost | $ 138,133,000 | $ 146,660,000
Gross Unrealized Gains | 391,000 | 1,932,000
Gross Unrealized Losses | (641,000) | (1,552,000)
Fair Value | 137,883,000 | 147,040,000
Collateralized Mortgage Backed Securities [Member] |  |
Amortized Cost | 51,671,000 | 66,670,000
Gross Unrealized Gains | 956,000 | 708,000
Gross Unrealized Losses | (58,000) | (304,000)
Fair Value | 52,569,000 | 67,074,000
Municipal General Obligation Bonds [Member] |  |
Amortized Cost | 122,293,000 | 120,679,000
Gross Unrealized Gains | 2,357,000 | 1,549,000
Gross Unrealized Losses | (164,000) | (205,000)
Fair Value | 124,486,000 | 122,023,000
Municipal Revenue Bonds [Member] |  |
Amortized Cost | 8,458,000 | 8,841,000
Gross Unrealized Gains | 70,000 | 76,000
Gross Unrealized Losses | (10,000) | (3,000)
Fair Value | 8,518,000 | 8,914,000
Other Debt Obligations [Member] |  |
Amortized Cost | 1,970,000 | 1,946,000
Gross Unrealized Gains | 17,000 | 0
Gross Unrealized Losses | 0 | (5,000)
Fair Value | 1,987,000 | 1,941,000
Amortized Cost | 322,525,000 | 344,796,000
Gross Unrealized Gains | 3,791,000 | 4,265,000
Gross Unrealized Losses | (873,000) | (2,069,000)
Fair Value | $ 325,443,000 | $ 346,992,000

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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=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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