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Note 3 - Securities - Available-for-sale Securities (Details) - USD ($) | Dec. 31, 2016 | Dec. 31, 2015
--- | --- | ---
Amortized Cost | $ 336,562,000 | $ 344,796,000
Gross Unrealized Gains | 927,000 | 4,265,000
Gross Unrealized Losses | (9,429,000) | (2,069,000)
Fair Value | 328,060,000 | 346,992,000
US Government Agencies Debt Securities [Member] |  |
Amortized Cost | 159,271,000 | 146,660,000
Gross Unrealized Gains | 106,000 | 1,932,000
Gross Unrealized Losses | (7,337,000) | (1,552,000)
Fair Value | 152,040,000 | 147,040,000
Collateralized Mortgage Backed Securities [Member] |  |
Amortized Cost | 47,329,000 | 66,670,000
Gross Unrealized Gains | 486,000 | 708,000
Gross Unrealized Losses | (423,000) | (304,000)
Fair Value | 47,392,000 | 67,074,000
Municipal General Obligation Bonds [Member] |  |
Amortized Cost | 120,284,000 | 120,679,000
Gross Unrealized Gains | 312,000 | 1,549,000
Gross Unrealized Losses | (1,549,000) | (205,000)
Fair Value | 119,047,000 | 122,023,000
Municipal Revenue Bonds [Member] |  |
Amortized Cost | 7,699,000 | 8,841,000
Gross Unrealized Gains | 23,000 | 76,000
Gross Unrealized Losses | (91,000) | (3,000)
Fair Value | 7,631,000 | 8,914,000
Other Debt Obligations [Member] |  |
Amortized Cost | 1,979,000 | 1,946,000
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | (29,000) | (5,000)
Fair Value | $ 1,950,000 | $ 1,941,000

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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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