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Note 6 - Investment and Equity Securities- Amortized Cost and Fair Values of Securities Available for Sale (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Amortized cost | [1] | $ 179,747 | $ 191,211
Gross unrealized gains |  | 152 | 72
Gross unrealized losses |  | (24,044) | (25,481)
Investment securities available for sale, at fair value |  | 155,855 | 165,802
Subordinated Debt Securities [Member] |  |  |
Amortized cost | [1] | 24,500 | 34,300
Gross unrealized gains |  | 85 | 67
Gross unrealized losses |  | (1,013) | (1,898)
Investment securities available for sale, at fair value |  | 23,572 | 32,469
Nontaxable Municipal Bonds [Member] |  |  |
Amortized cost | [1] | 146,851 | 147,767
Gross unrealized gains |  | 21 | 4
Gross unrealized losses |  | (22,499) | (22,805)
Investment securities available for sale, at fair value |  | 124,373 | 124,966
Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member] |  |  |
Amortized cost | [1] | 8,396 | 9,144
Gross unrealized gains |  | 46 | 1
Gross unrealized losses |  | (532) | (778)
Investment securities available for sale, at fair value |  | $ 7,910 | $ 8,367
[1] | Accrued interest of $1.5 million is excluded from amortized cost and presented in "accrued interest receivable and other assets" on the Consolidated Balance Sheet.

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- Definition Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) 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 2 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481800/320-10-50-2 + Details
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- Definition Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) 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 2 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481800/320-10-50-2 + Details
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- Definition Amortized cost excluding accrued interest, before allowance for credit loss, of 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 326 -SubTopic 30 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479130/326-30-45-1 + Details
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