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Note 5 - Securities (Details) - Temporarily Impaired Securities (USD $) In Thousands, unless otherwise specified | Sep. 30, 2014 | Dec. 31, 2013
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Note 5 - Securities (Details) - Temporarily Impaired Securities [Line Items] |  |
Less Than 12 Months - Fair Value | $ 17,782 | $ 202,015
Less Than 12 Months - Unrealized Loss | 137 | 27,059
12 Months or More - Fair Value | 192,173 | 18,493
12 Months or More - Unrealized Loss | 12,647 | 3,702
US Government Agencies [Member] |  |
Note 5 - Securities (Details) - Temporarily Impaired Securities [Line Items] |  |
Less Than 12 Months - Fair Value | 16,798 | 138,324
Less Than 12 Months - Unrealized Loss | 79 | 20,400
12 Months or More - Fair Value | 161,479 | 15,796
12 Months or More - Unrealized Loss | 11,260 | 3,211
States And Political Subdivisions [Member] |  |
Note 5 - Securities (Details) - Temporarily Impaired Securities [Line Items] |  |
Less Than 12 Months - Fair Value | 401 | 58,013
Less Than 12 Months - Unrealized Loss |  | 6,131
12 Months or More - Fair Value | 26,841 | 2,697
12 Months or More - Unrealized Loss | 1,212 | 491
Corporate Securities [Member] |  |
Note 5 - Securities (Details) - Temporarily Impaired Securities [Line Items] |  |
Less Than 12 Months - Fair Value | 450 | 5,511
Less Than 12 Months - Unrealized Loss | 2 | 506
12 Months or More - Fair Value | 3,853 |
12 Months or More - Unrealized Loss | 175 |
Other Securities [Member] |  |
Note 5 - Securities (Details) - Temporarily Impaired Securities [Line Items] |  |
Less Than 12 Months - Fair Value | 133 | 167
Less Than 12 Months - Unrealized Loss | $ 56 | $ 22

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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- 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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