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Note 7 - Investment Securities (Details Textual) $ in Thousands | 1 Months Ended | 3 Months Ended | 9 Months Ended |
--- | --- | --- | --- | ---
Mar. 31, 2023 USD ($) | Sep. 30, 2024 USD ($) | Sep. 30, 2023 USD ($) | Sep. 30, 2024 USD ($) | Sep. 30, 2023 USD ($) | Dec. 31, 2023 USD ($)
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss |  | $ 4,500 |  | $ 4,500 |  | $ 5,500
Equity Securities, FV-NI, Unrealized Gain (Loss) |  | 4,300 | $ (6,200) | (6,204) | $ 9,298 |
Equity Securities, FV-NI, Current |  | $ 35,741 |  | $ 35,741 |  | $ 40,406
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions |  | 177 |  | 177 |  | 192
Proceeds from Sale of Debt Securities, Available-for-Sale |  |  |  | $ 33,690 | $ 0 |
Debt Securities, Available-for-Sale, Allowance for Credit Loss |  | $ 0 |  | 0 |  |
Debt Securities, Available-for-Sale, Transfer in, Allowance for Credit Loss, Expense |  | 0 |  | 0 |  |
Pledged Investment Securities |  | $ 18,400 |  | 18,400 |  | $ 134,200
Signature Bank [Member] |  |  |  |  |  |
Debt Securities, Available-for-Sale, Realized Loss | $ 3,000 |  |  |  |  |
Proceeds from Sale of Debt Securities, Available-for-Sale |  |  |  | $ 1,400 |  |
Collateralized Mortgage-Backed Securities [Member] |  |  |  |  |  |
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions |  | 149 |  | 149 |  | 154
Corporate Debt Securities [Member] |  |  |  |  |  |
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions |  | 18 |  | 18 |  | 24
Collateralized Mortgage Obligations [Member] |  |  |  |  |  |
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions |  | 5 |  | 5 |  | 5
US Government Corporations and Agencies Securities [Member] |  |  |  |  |  |
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions |  | 5 |  | 5 |  | 8
US Treasury Securities [Member] |  |  |  |  |  |
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions |  |  |  |  |  | 1

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- Definition Amount, after allowance for credit loss, of accrued interest on 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 -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2A -Publisher FASB -URI https://asc.fasb.org/1943274/2147481800/320-10-50-2A Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479130/326-30-45-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 3A -Publisher FASB -URI https://asc.fasb.org/1943274/2147479106/326-30-50-3A Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 3B -Publisher FASB -URI https://asc.fasb.org/1943274/2147479106/326-30-50-3B + Details
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