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Note 13 - Fair Value Measurement - Quantitative Information (Details) $ in Thousands | Sep. 30, 2024 USD ($) | Jun. 30, 2024 USD ($) | Dec. 31, 2023 USD ($) | Sep. 30, 2023 USD ($) | Jun. 30, 2023 USD ($) | Dec. 31, 2022 USD ($)
--- | --- | --- | --- | --- | --- | ---
Servicing rights on sold loans, at fair value | $ 3,584 |  | $ 3,793 |  |  |
Fair Value, Recurring [Member] |  |  |  |  |  |
Servicing rights on sold loans, at fair value | 3,584 |  | 3,793 |  |  |
Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member] |  |  |  |  |  |
Servicing rights on sold loans, at fair value | 3,584 | $ 3,740 | 3,793 | $ 3,729 | $ 3,825 | $ 3,887
Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member] | Mortgage-Backed Securities, Issued by Private Enterprises [Member] |  |  |  |  |  |
Partnership investments | $ 17,095 | $ 17,231 | $ 27,469 | $ 29,192 | $ 29,378 | $ 29,599
Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member] | Measurement Input, Discount Rate [Member] | Weighted Average [Member] |  |  |  |  |  |
Sold loan servicing rights, measurement input | 10.92 |  |  |  |  |
Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member] | Valuation Technique, Discounted Cash Flow [Member] | Measurement Input, Constant Prepayment Rate [Member] | Weighted Average [Member] |  |  |  |  |  |
Sold loan servicing rights, measurement input | 7.83 |  | 7.39 |  |  |
Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member] | Valuation Technique, Discounted Cash Flow [Member] | Sold Loan Servicing Rights [Member] |  |  |  |  |  |
Servicing rights on sold loans, at fair value | $ 3,584 |  | $ 3,793 |  |  |
Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member] | Valuation Technique, Consensus Pricing Model [Member] | Mortgage-Backed Securities, Issued by Private Enterprises [Member] |  |  |  |  |  |
Assets, fair value | 17,095 |  | 27,469 |  |  |
Partnership investments | $ 12,650 |  | $ 13,183 |  |  |
Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member] | Valuation Technique, Consensus Pricing Model [Member] | Measurement Input, Offered Price [Member] | Minimum [Member] |  |  |  |  |  |
Measurement input | 99 |  | 98 |  |  |
Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member] | Valuation Technique, Consensus Pricing Model [Member] | Measurement Input, Offered Price [Member] | Maximum [Member] |  |  |  |  |  |
Measurement input | 100 |  | 100 |  |  |

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- Definition Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 860 -SubTopic 50 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (a)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481229/860-50-50-3 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 860 -SubTopic 50 -Name Accounting Standards Codification -Section 45 -Paragraph 2 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481260/860-50-45-2 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 860 -SubTopic 50 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481260/860-50-45-1 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Topic 860 -SubTopic 50 -Name Accounting Standards Codification -Section 45 -Paragraph 2 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481260/860-50-45-2 + Details
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