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Note 5 - Mortgage Servicing Rights - Valuation Assumptions (Details) - Mortgage Servicing Rights [Member] | 12 Months Ended
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Dec. 31, 2023 | Dec. 31, 2022
Weighted average discount rate | 9.40% | 9.60%
Conditional prepayment rate (“CPR”) | 7.20% | 8.20%
Weighted average life in years (Year) | 8 years 4 months 24 days | 7 years 9 months 18 days

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- Definition Discount rate used to estimate the fair value of servicing assets and servicing liabilities. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 860 -SubTopic 50 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481229/860-50-50-2 + Details
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- Definition Estimated rate of prepayments of principal on servicing assets and servicing liabilities. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 860 -SubTopic 50 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481229/860-50-50-2 + Details
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- Definition Weighted average life of financial assets and financial liabilities, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 860 -SubTopic 50 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481229/860-50-50-2 + Details
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