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Note 11 - Fair Values (Details Textual) - USD ($) | 9 Months Ended |
--- | --- | ---
Sep. 30, 2021 | Dec. 31, 2020
Debt Securities, Available-for-sale, Total | $ 559,564,000 | $ 387,347,000
Mortgages Held-for-sale, Fair Value Disclosure | $ 49,100,000 | 24,000,000.0
Real Estate Dependent Loans and Foreclosed Assets Estimated Selling Costs [Member] |  |
Fair Value Inputs, Discount Factor | 10.00% |
Real Estate Dependent Loans and Foreclosed Assets [Member] | Commercial Real Estate [Member] | Minimum [Member] |  |
Fair Value Inputs, Discount Factor | 15.00% |
Real Estate Dependent Loans and Foreclosed Assets [Member] | Commercial Real Estate [Member] | Maximum [Member] |  |
Fair Value Inputs, Discount Factor | 25.00% |
Real Estate Dependent Loans and Foreclosed Assets [Member] | Residential Real Estate [Member] | Minimum [Member] |  |
Fair Value Inputs, Discount Factor | 25.00% |
Real Estate Dependent Loans and Foreclosed Assets [Member] | Residential Real Estate [Member] | Maximum [Member] |  |
Fair Value Inputs, Discount Factor | 50.00% |
Municipal General Obligation Bonds [Member] |  |
Debt Securities, Available-for-sale, Total | $ 134,610,000 | 107,824,000
Fair Value, Inputs, Level 1 [Member] |  |
Debt Securities, Available-for-sale, Total | 0 | 0
Fair Value, Inputs, Level 3 [Member] | Municipal General Obligation Bonds [Member] |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements | 100,000 |
Available-for-sale Securities [Member] |  |
SEC Schedule, 12-09, Valuation Allowances and Reserves, Amount, Ending Balance | $ 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). + References Reference 1: 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 http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=124260329&loc=d3e26610-111562 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27161-111563 + Details
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