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Note 2 - Securities - Securities in a Continuous Loss Position (Details) - USD ($) $ in Thousands | Dec. 31, 2024 | Dec. 31, 2023
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Securities available for sale, continuous unrealized loss position, less than 12 months | $ 180,363 | $ 2,729
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 3,525 | 14
Securities available for sale, continuous unrealized loss position, 12 months or more | 500,054 | 546,018
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 60,282 | 66,098
Securities available for sale, continuous unrealized loss position | 680,417 | 548,747
Securities available for sale, continuous unrealized loss position, unrealized loss | 63,807 | 66,112
US Government Agencies Debt Securities [Member] |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | 113,942 | 0
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 2,379 | 0
Securities available for sale, continuous unrealized loss position, 12 months or more | 361,171 | 390,496
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 44,847 | 52,000
Securities available for sale, continuous unrealized loss position | 475,113 | 390,496
Securities available for sale, continuous unrealized loss position, unrealized loss | 47,226 | 52,000
Collateralized Mortgage-Backed Securities [Member] |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | 194 | 114
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 1 | 0
Securities available for sale, continuous unrealized loss position, 12 months or more | 24,865 | 28,749
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 6,331 | 5,715
Securities available for sale, continuous unrealized loss position | 25,059 | 28,863
Securities available for sale, continuous unrealized loss position, unrealized loss | 6,332 | 5,715
Municipal General Obligation Bonds [Member] |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | 63,387 | 1,109
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 1,117 | 6
Securities available for sale, continuous unrealized loss position, 12 months or more | 92,153 | 106,171
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 6,710 | 6,184
Securities available for sale, continuous unrealized loss position | 155,540 | 107,280
Securities available for sale, continuous unrealized loss position, unrealized loss | 7,827 | 6,190
Municipal Revenue Bonds [Member] |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | 2,840 | 1,506
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 28 | 8
Securities available for sale, continuous unrealized loss position, 12 months or more | 21,865 | 20,602
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 2,394 | 2,199
Securities available for sale, continuous unrealized loss position | 24,705 | 22,108
Securities available for sale, continuous unrealized loss position, unrealized loss | 2,422 | 2,207
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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