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Note 2 - Securities - Available-for-sale Securities (Details) - USD ($) | Dec. 31, 2022 | Dec. 31, 2021
--- | --- | ---
Amortized cost | $ 685,646,000 | $ 597,463,000
Securities available for sale, gross unrealized gains | 571,000 | 5,238,000
Securities available for sale, gross unrealized losses | (83,281,000) | (9,958,000)
Fair value | 602,936,000 | 592,743,000
US Government Agencies Debt Securities [Member] |  |
Amortized cost | 453,836,000 | 398,874,000
Securities available for sale, gross unrealized gains | 0 | 266,000
Securities available for sale, gross unrealized losses | (65,092,000) | (8,769,000)
Fair value | 388,744,000 | 390,371,000
Collateralized Mortgage-Backed Securities [Member] |  |
Amortized cost | 38,002,000 | 41,906,000
Securities available for sale, gross unrealized gains | 19,000 | 549,000
Securities available for sale, gross unrealized losses | (6,068,000) | (652,000)
Fair value | 31,953,000 | 41,803,000
Municipal General Obligation Bonds [Member] |  |
Amortized cost | 163,041,000 | 133,894,000
Securities available for sale, gross unrealized gains | 450,000 | 4,092,000
Securities available for sale, gross unrealized losses | (9,058,000) | (392,000)
Fair value | 154,433,000 | 137,594,000
Municipal Revenue Bonds [Member] |  |
Amortized cost | 30,267,000 | 22,289,000
Securities available for sale, gross unrealized gains | 102,000 | 331,000
Securities available for sale, gross unrealized losses | (3,063,000) | (145,000)
Fair value | 27,306,000 | 22,475,000
Other Debt and Equity Securities [Member] |  |
Amortized cost | 500,000 | 500,000
Securities available for sale, gross unrealized gains | 0 | 0
Securities available for sale, gross unrealized losses | 0 | 0
Fair value | $ 500,000 | $ 500,000

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