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Note 2 - Securities - Securities in a Continuous Loss Position (Details) - USD ($) $ in Thousands | Mar. 31, 2025 | Dec. 31, 2024
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Securities available for sale, continuous unrealized loss position, less than 12 months | $ 130,860 | $ 180,363
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 2,192 | 3,525
Securities available for sale, continuous unrealized loss position, 12 months or more | 509,083 | 500,054
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 51,275 | 60,282
Securities available for sale, continuous unrealized loss position | 639,943 | 680,417
Securities available for sale, continuous unrealized loss position, unrealized loss | 53,467 | 63,807
US Government Agencies Debt Securities [Member] |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | 76,302 | 113,942
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 685 | 2,379
Securities available for sale, continuous unrealized loss position, 12 months or more | 361,528 | 361,171
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 37,018 | 44,847
Securities available for sale, continuous unrealized loss position | 437,830 | 475,113
Securities available for sale, continuous unrealized loss position, unrealized loss | 37,703 | 47,226
Collateralized Mortgage-Backed Securities [Member] |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | 12 | 194
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 0 | 1
Securities available for sale, continuous unrealized loss position, 12 months or more | 24,625 | 24,865
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 5,674 | 6,331
Securities available for sale, continuous unrealized loss position | 24,637 | 25,059
Securities available for sale, continuous unrealized loss position, unrealized loss | 5,674 | 6,332
Municipal General Obligation Bonds [Member] |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | 52,177 | 63,387
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 1,486 | 1,117
Securities available for sale, continuous unrealized loss position, 12 months or more | 101,963 | 92,153
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 6,367 | 6,710
Securities available for sale, continuous unrealized loss position | 154,140 | 155,540
Securities available for sale, continuous unrealized loss position, unrealized loss | 7,853 | 7,827
Municipal Revenue Bonds [Member] |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | 2,369 | 2,840
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 21 | 28
Securities available for sale, continuous unrealized loss position, 12 months or more | 20,967 | 21,865
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 2,216 | 2,394
Securities available for sale, continuous unrealized loss position | 23,336 | 24,705
Securities available for sale, continuous unrealized loss position, unrealized loss | 2,237 | 2,422
Other Debt and Equity Securities [Member] |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | 0 | 0
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 0 | 0
Securities available for sale, continuous unrealized loss position, 12 months or more | 0 | 0
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 0 | 0
Securities available for sale, continuous unrealized loss position | 0 | 0
Securities available for sale, continuous unrealized loss position, unrealized loss | $ 0 | $ 0

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