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Note 2 - Securities - Available-for-sale Securities (Details) - USD ($) $ in Thousands | Dec. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Total, amortized cost | $ 793,422 | $ 680,998
Securities available for sale, gross unrealized gains | 737 | 2,206
Securities available for sale, gross unrealized losses | (63,807) | (66,112)
Fair value | 730,352 | 617,092
US Government Agencies Debt Securities [Member] |  |
Total, amortized cost | 542,676 | 442,496
Securities available for sale, gross unrealized gains | 131 | 0
Securities available for sale, gross unrealized losses | (47,226) | (52,000)
Fair value | 495,581 | 390,496
Collateralized Mortgage-Backed Securities [Member] |  |
Total, amortized cost | 31,696 | 35,168
Securities available for sale, gross unrealized gains | 4 | 20
Securities available for sale, gross unrealized losses | (6,332) | (5,715)
Fair value | 25,368 | 29,473
Municipal General Obligation Bonds [Member] |  |
Total, amortized cost | 187,484 | 172,126
Securities available for sale, gross unrealized gains | 513 | 1,924
Securities available for sale, gross unrealized losses | (7,827) | (6,190)
Fair value | 180,170 | 167,860
Municipal Revenue Bonds [Member] |  |
Total, amortized cost | 31,066 | 30,708
Securities available for sale, gross unrealized gains | 89 | 262
Securities available for sale, gross unrealized losses | (2,422) | (2,207)
Fair value | 28,733 | 28,763
Other Debt and Equity Securities [Member] |  |
Total, amortized cost | 500 | 500
Securities available for sale, gross unrealized gains | 0 | 0
Securities available for sale, gross unrealized losses | 0 | 0
Fair value | $ 500 | $ 500

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