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Note 14 - Concentrations of Credit Risk (Details Textual) - Credit Concentration Risk [Member] - Commercial Real Estate, Loan Portfolio [Member] - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2025 | Dec. 31, 2024
Residential Real Estate Loans [Member] |  |
Concentration Risk [Line Items] |  |
Concentration Risk, Credit Risk, Financial Instrument, Maximum Exposure | $ 328,653 | $ 307,855
Concentration Risk, Percentage | 33.00% | 31.00%
Commercial Real Estate Loans [Member] |  |
Concentration Risk [Line Items] |  |
Concentration Risk, Credit Risk, Financial Instrument, Maximum Exposure | $ 467,783 | $ 478,078
Concentration Risk, Percentage | 47.00% | 48.00%
College Housing and Professional Office Buildings [Member] |  |
Concentration Risk [Line Items] |  |
Concentration Risk, Credit Risk, Financial Instrument, Maximum Exposure | $ 168,609 | $ 191,026
Concentration Risk, Percentage | 17.00% | 19.00%

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- Definition Maximum amount of loss due to credit risk that, based on the gross fair value of the financial instrument, the entity would incur if parties to the financial instruments that make up the concentration failed completely to perform according to the terms of the contracts and the collateral or other security, if any, for the amount due proved to be of no value to the entity. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 825 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 21 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482907/825-10-50-21 + Details
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