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Note 3 - Loans and Allowance for Credit Losses - Loans Modified As Troubled Debt Restructurings Within the Previous Twelve Months That Became Over 30 Days Past Due (Details) | 3 Months Ended
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Mar. 31, 2022 USD ($) | Mar. 31, 2021 USD ($)
Number of Contracts | 0 | 3
Recorded Principal Balance | $ 0 | $ 599,000
Commercial Portfolio Segment [Member] |  |
Number of Contracts | 0 | 2
Recorded Principal Balance | $ 0 | $ 593,000
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |
Number of Contracts | 0 | 2
Recorded Principal Balance | $ 0 | $ 593,000
Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |
Number of Contracts | 0 | 0
Recorded Principal Balance | $ 0 | $ 0
Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member] |  |
Number of Contracts | 0 | 0
Recorded Principal Balance | $ 0 | $ 0
Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member] |  |
Number of Contracts | 0 | 0
Recorded Principal Balance | $ 0 | $ 0
Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member] |  |
Number of Contracts | 0 | 0
Recorded Principal Balance | $ 0 | $ 0
Retail Portfolio Segment [Member] |  |
Number of Contracts | 0 | 1
Recorded Principal Balance | $ 0 | $ 6,000
Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member] |  |
Number of Contracts | 0 | 1
Recorded Principal Balance | $ 0 | $ 6,000
Retail Portfolio Segment [Member] | Other Consumer Loans [Member] |  |
Number of Contracts | 0 | 0
Recorded Principal Balance | $ 0 | $ 0

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- Definition Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 34 -URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953682-111524 + Details
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- Definition Amount of financing receivable modified as troubled debt restructuring within previous 12 months, with subsequent payment default. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 34 -Subparagraph (a)(2) -URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953682-111524 + Details
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