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Note 2 - Securities (Details Textual) - USD ($) $ in Thousands | 3 Months Ended
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Mar. 31, 2022 | Mar. 31, 2021
Debt Securities, Held-to-Maturity, Fair Value, Total | $ 397,911 |
Other-than-temporary Impairment Loss, Debt Securities, Available-for-Sale | 0 | $ 0
Reclassified From Available-for-sale Securities [Member] |  |
Debt Securities, Held-to-Maturity, Fair Value, Total | 428,400 |
OCI, Debt Securities, Available-for-Sale, Transfer to Held-to-Maturity, Adjustment from AOCI for Amortization of Gain (Loss), after Tax | (3,400) |
OCI, Debt Securities, Available-for-Sale, Transfer to Held-to-Maturity, Adjustment from AOCI Unamortized, After Tax | $ 2,600 |

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- Definition Amount, after tax, of adjustment from accumulated other comprehensive income (loss) stay unamortized on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) from transfer to investment in debt security measured at amortized cost (held-to-maturity). + References No definition available. + Details
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- Definition Fair value of investment in debt security measured at amortized cost (held-to-maturity). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (aa) -URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27232-111563 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(6)) -URI https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5A -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=126970911&loc=SL120269820-111563 + Details
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