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Note 2 - Securities - Securities in a Continuous Loss Position (Details) - USD ($) | Dec. 31, 2022 | Dec. 31, 2021
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Securities available for sale, continuous unrealized loss position, less than 12 months | $ 193,930,000 | $ 351,062,000
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 17,438,000 | 6,455,000
Securities available for sale, continuous unrealized loss position, 12 months or more | 379,216,000 | 110,491,000
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 65,843,000 | 3,503,000
Securities available for sale, continuous unrealized loss position | 573,146,000 | 461,553,000
Securities available for sale, continuous unrealized loss position, unrealized loss | 83,281,000 | 9,958,000
US Government Agencies Debt Securities [Member] |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | 53,019,000 | 274,287,000
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 5,713,000 | 5,274,000
Securities available for sale, continuous unrealized loss position, 12 months or more | 335,725,000 | 110,053,000
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 59,379,000 | 3,495,000
Securities available for sale, continuous unrealized loss position | 388,744,000 | 384,340,000
Securities available for sale, continuous unrealized loss position, unrealized loss | 65,092,000 | 8,769,000
Collateralized Mortgage-Backed Securities [Member] |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | 31,127,000 | 23,184,000
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 6,068,000 | 652,000
Securities available for sale, continuous unrealized loss position, 12 months or more | 12,000 | 24,000
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 0 | 0
Securities available for sale, continuous unrealized loss position | 31,139,000 | 23,208,000
Securities available for sale, continuous unrealized loss position, unrealized loss | 6,068,000 | 652,000
Municipal General Obligation Bonds [Member] |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | 97,252,000 | 40,748,000
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 4,516,000 | 392,000
Securities available for sale, continuous unrealized loss position, 12 months or more | 32,870,000 | 0
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 4,542,000 | 0
Securities available for sale, continuous unrealized loss position | 130,122,000 | 40,748,000
Securities available for sale, continuous unrealized loss position, unrealized loss | 9,058,000 | 392,000
Municipal Revenue Bonds [Member] |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | 12,532,000 | 12,843,000
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 1,141,000 | 137,000
Securities available for sale, continuous unrealized loss position, 12 months or more | 10,609,000 | 414,000
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 1,922,000 | 8,000
Securities available for sale, continuous unrealized loss position | 23,141,000 | 13,257,000
Securities available for sale, continuous unrealized loss position, unrealized loss | 3,063,000 | 145,000
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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