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Note 2 - Securities - Securities in a Continuous Loss Position (Details) - USD ($) | Jun. 30, 2020 | Dec. 31, 2019
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Securities available for sale, continuous unrealized loss position, less than 12 months | $ 16,370,000 | $ 32,243,000
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 35,000 | 395,000
Securities available for sale, continuous unrealized loss position, 12 months or more | 26,000 | 85,330,000
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 1,000 | 859,000
Securities available for sale, continuous unrealized loss position | 16,396,000 | 117,573,000
Securities available for sale, continuous unrealized loss position, unrealized loss | 36,000 | 1,254,000
US Government Agencies Debt Securities [Member] |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | 16,370,000 | 25,650,000
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 35,000 | 349,000
Securities available for sale, continuous unrealized loss position, 12 months or more | 0 | 73,913,000
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 0 | 793,000
Securities available for sale, continuous unrealized loss position | 16,370,000 | 99,563,000
Securities available for sale, continuous unrealized loss position, unrealized loss | 35,000 | 1,142,000
Collateralized Mortgage Backed Securities [Member] |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | 0 | 2,838,000
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 0 | 28,000
Securities available for sale, continuous unrealized loss position, 12 months or more | 26,000 | 10,423,000
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 1,000 | 54,000
Securities available for sale, continuous unrealized loss position | 26,000 | 13,261,000
Securities available for sale, continuous unrealized loss position, unrealized loss | 1,000 | 82,000
Municipal General Obligation Bonds [Member] |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | 0 | 3,755,000
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 0 | 18,000
Securities available for sale, continuous unrealized loss position, 12 months or more | 0 | 994,000
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 0 | 12,000
Securities available for sale, continuous unrealized loss position | 0 | 4,749,000
Securities available for sale, continuous unrealized loss position, unrealized loss | 0 | 30,000
Municipal Revenue Bonds [Member] |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | 0 | 0
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 0 | 0
Securities available for sale, continuous unrealized loss position, 12 months or more | 0 | 0
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 0 | 0
Securities available for sale, continuous unrealized loss position | 0 | 0
Securities available for sale, continuous unrealized loss position, unrealized loss | $ 0 | $ 0

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- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=121582814&loc=SL82922890-210455 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27337-111563 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=121590138&loc=SL82922954-210456 + Details
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