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Note 2 - Securities - Securities in a Continuous Loss Position (Details) - USD ($) $ in Thousands | Jun. 30, 2025 | Dec. 31, 2024
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Securities available for sale, continuous unrealized loss position, less than 12 months | $ 90,319 | $ 180,363
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 1,944 | 3,525
Securities available for sale, continuous unrealized loss position, 12 months or more | 513,805 | 500,054
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 46,288 | 60,282
Securities available for sale, continuous unrealized loss position | 604,124 | 680,417
Securities available for sale, continuous unrealized loss position, unrealized loss | 48,232 | 63,807
US Government Agencies Debt Securities [Member] |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | 49,087 | 113,942
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 454 | 2,379
Securities available for sale, continuous unrealized loss position, 12 months or more | 359,282 | 361,171
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 32,865 | 44,847
Securities available for sale, continuous unrealized loss position | 408,369 | 475,113
Securities available for sale, continuous unrealized loss position, unrealized loss | 33,319 | 47,226
Collateralized Mortgage-Backed Securities [Member] |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | 0 | 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 | 23,848 | 24,865
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 5,523 | 6,331
Securities available for sale, continuous unrealized loss position | 23,848 | 25,059
Securities available for sale, continuous unrealized loss position, unrealized loss | 5,523 | 6,332
Municipal General Obligation Bonds [Member] |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | 38,247 | 63,387
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 1,449 | 1,117
Securities available for sale, continuous unrealized loss position, 12 months or more | 108,089 | 92,153
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 5,912 | 6,710
Securities available for sale, continuous unrealized loss position | 146,336 | 155,540
Securities available for sale, continuous unrealized loss position, unrealized loss | 7,361 | 7,827
Municipal Revenue Bonds [Member] |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | 2,985 | 2,840
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 41 | 28
Securities available for sale, continuous unrealized loss position, 12 months or more | 22,586 | 21,865
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 1,988 | 2,394
Securities available for sale, continuous unrealized loss position | 25,571 | 24,705
Securities available for sale, continuous unrealized loss position, unrealized loss | 2,029 | 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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