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Note 5 - Securities (Details) - Securities in a Continuous Loss Position - USD ($) $ in Thousands | Jun. 30, 2015 | Dec. 31, 2014
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Temporarily Impaired Securities: |  |
Securities in a continuous loss position, less than 12 months, fair value | $ 113,660 | $ 8,636
Securities in a continuous loss position, less than 12 months, unrealized loss | 4,344 | 67
Securities in a continuous loss position, 12 months or more, fair value | 98,516 | 178,042
Securities in a continuous loss position, 12 months or more, unrealized loss | 6,593 | 5,490
US Government Agencies Debt Securities [Member] |  |
Temporarily Impaired Securities: |  |
Securities in a continuous loss position, less than 12 months, fair value | 81,425 | 6,964
Securities in a continuous loss position, less than 12 months, unrealized loss | 2,993 | 30
Securities in a continuous loss position, 12 months or more, fair value | 88,618 | 156,149
Securities in a continuous loss position, 12 months or more, unrealized loss | 5,666 | 4,709
US States and Political Subdivisions Debt Securities [Member] |  |
Temporarily Impaired Securities: |  |
Securities in a continuous loss position, less than 12 months, fair value | 27,353 | 1,222
Securities in a continuous loss position, less than 12 months, unrealized loss | 965 | 35
Securities in a continuous loss position, 12 months or more, fair value | 9,509 | 19,818
Securities in a continuous loss position, 12 months or more, unrealized loss | 873 | 692
Corporate Debt Securities [Member] |  |
Temporarily Impaired Securities: |  |
Securities in a continuous loss position, less than 12 months, fair value | 4,882 | 450
Securities in a continuous loss position, less than 12 months, unrealized loss | 386 | 2
Securities in a continuous loss position, 12 months or more, fair value | 200 | 1,948
Securities in a continuous loss position, 12 months or more, unrealized loss | 1 | 27
Other Debt Obligations [Member] |  |
Temporarily Impaired Securities: |  |
Securities in a continuous loss position, 12 months or more, fair value | 189 | 127
Securities in a continuous loss position, 12 months or more, unrealized loss | $ 53 | $ 62

X
- Definition Amount of the excess of amortized cost basis over fair value of securities that have been in a loss position for twelve months or longer for securities. + References No definition available. + Details
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X
- Definition Amount of the excess of amortized cost basis over fair value of securities that have been in a loss position for less than twelve months for securities. + References No definition available. + Details
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X
- Definition This item represents the aggregate fair value of investments in debt and equity securities that have been in a continuous unrealized loss position for less than twelve months. + References No definition available. + Details
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X
- Definition This item represents the aggregate fair value of investments in debt and equity securities that have been in a continuous unrealized loss position for twelve months or longer. + References No definition available. + Details
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