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Note 2 - Securities - Securities in a Continuous Loss Position (Details) - USD ($) | Mar. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Securities available for sale, continuous unrealized loss position, less than 12 months | $ 262,853,000 | $ 119,073,000
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 8,331,000 | 899,000
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 | 262,853,000 | 119,073,000
Securities available for sale, continuous unrealized loss position, unrealized loss | 8,331,000 | 899,000
US Government Agencies Debt Securities [Member] |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | 234,832,000 | 118,650,000
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 7,572,000 | 897,000
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 | 234,832,000 | 118,650,000
Securities available for sale, continuous unrealized loss position, unrealized loss | 7,572,000 | 897,000
Collateralized Mortgage Backed Securities [Member] |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | 7,264,000 | 0
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 328,000 | 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 | 7,264,000 | 0
Securities available for sale, continuous unrealized loss position, unrealized loss | 328,000 | 0
Municipal General Obligation Bonds [Member] |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | 13,961,000 | 0
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 274,000 | 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 | 13,961,000 | 0
Securities available for sale, continuous unrealized loss position, unrealized loss | 274,000 | 0
Municipal Revenue Bonds [Member] |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | 6,796,000 | 423,000
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 157,000 | 2,000
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 | 6,796,000 | 423,000
Securities available for sale, continuous unrealized loss position, unrealized loss | $ 157,000 | $ 2,000

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