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Note 6 - Investment and Equity Securities- Amortized Cost and Fair Values of Securities Available for Sale (Details) - USD ($) $ in Thousands | Mar. 31, 2025 | Dec. 31, 2024
--- | --- | ---
Amortized cost | [1] | $ 190,887 | $ 191,211
Gross unrealized gains |  | 115 | 72
Gross unrealized losses |  | (25,988) | (25,481)
Investment securities available for sale, at fair value |  | 165,014 | 165,802
Subordinated Debt Securities [Member] |  |  |
Amortized cost | [1] | 34,300 | 34,300
Gross unrealized gains |  | 86 | 67
Gross unrealized losses |  | (1,557) | (1,898)
Investment securities available for sale, at fair value |  | 32,829 | 32,469
Nontaxable Municipal Bonds [Member] |  |  |
Amortized cost | [1] | 147,634 | 147,767
Gross unrealized gains |  | 4 | 4
Gross unrealized losses |  | (23,787) | (22,805)
Investment securities available for sale, at fair value |  | 123,851 | 124,966
Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member] |  |  |
Amortized cost | [1] | 8,953 | 9,144
Gross unrealized gains |  | 25 | 1
Gross unrealized losses |  | (644) | (778)
Investment securities available for sale, at fair value |  | $ 8,334 | $ 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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