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Note 2 - Securities - Securities in a Continuous Loss Position (Details) - USD ($) | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Securities available for sale, continuous unrealized loss position, less than 12 months | $ 119,073,000 | $ 32,243,000
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 899,000 | 395,000
Securities available for sale, continuous unrealized loss position, 12 months or more | 0 | 85,330,000
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 0 | 859,000
Securities available for sale, continuous unrealized loss position | 119,073,000 | 117,573,000
Securities available for sale, continuous unrealized loss position, unrealized loss | 899,000 | 1,254,000
US Government Agencies Debt Securities [Member] |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | 118,650,000 | 25,650,000
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 897,000 | 349,000
Securities available for sale, continuous unrealized loss position, 12 months or more | 0 | 73,913,000
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 0 | 793,000
Securities available for sale, continuous unrealized loss position | 118,650,000 | 99,563,000
Securities available for sale, continuous unrealized loss position, unrealized loss | 897,000 | 1,142,000
Collateralized Mortgage Backed Securities [Member] |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | 0 | 2,838,000
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 0 | 28,000
Securities available for sale, continuous unrealized loss position, 12 months or more | 0 | 10,423,000
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 0 | 54,000
Securities available for sale, continuous unrealized loss position | 0 | 13,261,000
Securities available for sale, continuous unrealized loss position, unrealized loss | 0 | 82,000
Municipal General Obligation Bonds [Member] |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | 0 | 3,755,000
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 0 | 18,000
Securities available for sale, continuous unrealized loss position, 12 months or more | 0 | 994,000
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 0 | 12,000
Securities available for sale, continuous unrealized loss position | 0 | 4,749,000
Securities available for sale, continuous unrealized loss position, unrealized loss | 0 | 30,000
Municipal Revenue Bonds [Member] |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | 423,000 | 0
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 2,000 | 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 | 423,000 | 0
Securities available for sale, continuous unrealized loss position, unrealized loss | 2,000 | 0
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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