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Note 18 - Fair Value Measurements (Details Textual) - USD ($) | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019
AOCI, Debt Securities, Available-for-sale, Adjustment, after Tax, Total | $ 13,959,000 | $ 1,713,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases | 1,642,000 | 2,091,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Acquisition |  | 2,756,000
Fair Value, Inputs, Level 3 [Member] |  |
AOCI, Debt Securities, Available-for-sale, Adjustment, after Tax, Total | $ 889,000 | $ 324,000

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- Definition Amount of acquisition of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References No definition available. + Details
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- Definition Amount, after tax, of accumulated unrealized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14 -URI http://asc.fasb.org/extlink&oid=121641772&loc=d3e681-108580 + Details
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- Definition Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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