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Note 2 - Securities - Securities in a Continuous Loss Position (Details) - USD ($) | Jun. 30, 2019 | Dec. 31, 2018
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Securities available for sale, continuous unrealized loss position, less than 12 months | $ 797,000 | $ 72,791,000
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 4,000 | 1,582,000
Securities available for sale, continuous unrealized loss position, 12 months or more | 112,083,000 | 205,540,000
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 1,699,000 | 9,775,000
Securities available for sale, continuous unrealized loss position | 112,880,000 | 278,331,000
Securities available for sale, continuous unrealized loss position, unrealized loss | 1,703,000 | 11,357,000
US Government Agencies Debt Securities [Member] |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | 0 | 31,220,000
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 0 | 1,136,000
Securities available for sale, continuous unrealized loss position, 12 months or more | 82,942,000 | 136,445,000
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 1,498,000 | 8,206,000
Securities available for sale, continuous unrealized loss position | 82,942,000 | 167,665,000
Securities available for sale, continuous unrealized loss position, unrealized loss | 1,498,000 | 9,342,000
Collateralized Mortgage Backed Securities [Member] |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | 0 | 11,460,000
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 0 | 136,000
Securities available for sale, continuous unrealized loss position, 12 months or more | 20,419,000 | 23,762,000
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 142,000 | 656,000
Securities available for sale, continuous unrealized loss position | 20,419,000 | 35,222,000
Securities available for sale, continuous unrealized loss position, unrealized loss | 142,000 | 792,000
Municipal General Obligation Bonds [Member] |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | 797,000 | 28,923,000
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 4,000 | 299,000
Securities available for sale, continuous unrealized loss position, 12 months or more | 7,614,000 | 43,961,000
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 54,000 | 866,000
Securities available for sale, continuous unrealized loss position | 8,411,000 | 72,884,000
Securities available for sale, continuous unrealized loss position, unrealized loss | 58,000 | 1,165,000
Municipal Revenue Bonds [Member] |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | 0 | 1,188,000
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 0 | 11,000
Securities available for sale, continuous unrealized loss position, 12 months or more | 1,108,000 | 1,372,000
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 5,000 | 47,000
Securities available for sale, continuous unrealized loss position | 1,108,000 | 2,560,000
Securities available for sale, continuous unrealized loss position, unrealized loss | 5,000 | 58,000
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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