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Note 2 - Securities - Securities in a Continuous Loss Position (Details) - USD ($) | Dec. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Securities available for sale, continuous unrealized loss position, less than 12 months | $ 351,062,000 | $ 119,073,000
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 6,455,000 | 899,000
Securities available for sale, continuous unrealized loss position, 12 months or more | 110,491,000 | 0
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 3,503,000 | 0
Securities available for sale, continuous unrealized loss position | 461,553,000 | 119,073,000
Securities available for sale, continuous unrealized loss position, unrealized loss | 9,958,000 | 899,000
US Government Agencies Debt Securities [Member] |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | 274,287,000 | 118,650,000
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 5,274,000 | 897,000
Securities available for sale, continuous unrealized loss position, 12 months or more | 110,053,000 | 0
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 3,495,000 | 0
Securities available for sale, continuous unrealized loss position | 384,340,000 | 118,650,000
Securities available for sale, continuous unrealized loss position, unrealized loss | 8,769,000 | 897,000
Collateralized Mortgage Backed Securities [Member] |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | 23,184,000 | 0
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 652,000 | 0
Securities available for sale, continuous unrealized loss position, 12 months or more | 24,000 | 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 | 23,208,000 | 0
Securities available for sale, continuous unrealized loss position, unrealized loss | 652,000 | 0
Municipal General Obligation Bonds [Member] |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | 40,748,000 | 0
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 392,000 | 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 | 40,748,000 | 0
Securities available for sale, continuous unrealized loss position, unrealized loss | 392,000 | 0
Municipal Revenue Bonds [Member] |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | 12,843,000 | 423,000
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 137,000 | 2,000
Securities available for sale, continuous unrealized loss position, 12 months or more | 414,000 | 0
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 8,000 | 0
Securities available for sale, continuous unrealized loss position | 13,257,000 | 423,000
Securities available for sale, continuous unrealized loss position, unrealized loss | 145,000 | 2,000
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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