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Note 3 - Securities (Details) - Securities in a Continuous Loss Position - USD ($) | Dec. 31, 2015 | Dec. 31, 2014
--- | --- | ---
2015 |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | $ 21,452,000 | $ 190,579,000
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 78,000 | 740,000
Securities available for sale, continuous unrealized loss position, 12 months or more | 142,424,000 | 74,120,000
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 1,991,000 | 2,836,000
Securities available for sale, continuous unrealized loss position | 163,876,000 | 264,699,000
Securities available for sale, continuous unrealized loss position, unrealized loss | 2,069,000 | 3,576,000
US Government Agencies Debt Securities [Member] |  |
2015 |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | 0 | 81,891,000
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 0 | 202,000
Securities available for sale, continuous unrealized loss position, 12 months or more | 76,496,000 | 74,120,000
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 1,552,000 | 2,836,000
Securities available for sale, continuous unrealized loss position | 76,496,000 | 156,011,000
Securities available for sale, continuous unrealized loss position, unrealized loss | 1,552,000 | 3,038,000
Collateralized Mortgage Backed Securities [Member] |  |
2015 |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | 18,025,000 | 49,940,000
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 69,000 | 218,000
Securities available for sale, continuous unrealized loss position, 12 months or more | 34,660,000 | 0
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 235,000 | 0
Securities available for sale, continuous unrealized loss position | 52,685,000 | 49,940,000
Securities available for sale, continuous unrealized loss position, unrealized loss | 304,000 | 218,000
Municipal General Obligation Bonds [Member] |  |
2015 |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | 1,981,000 | 54,104,000
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 4,000 | 307,000
Securities available for sale, continuous unrealized loss position, 12 months or more | 30,134,000 | 0
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 201,000 | 0
Securities available for sale, continuous unrealized loss position | 32,115,000 | 54,104,000
Securities available for sale, continuous unrealized loss position, unrealized loss | 205,000 | 307,000
Municipal Revenue Bonds [Member] |  |
2015 |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | 0 | 4,644,000
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 0 | 13,000
Securities available for sale, continuous unrealized loss position, 12 months or more | 1,134,000 | 0
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 3,000 | 0
Securities available for sale, continuous unrealized loss position | 1,134,000 | 4,644,000
Securities available for sale, continuous unrealized loss position, unrealized loss | 3,000 | 13,000
Other Debt Obligations [Member] |  |
2015 |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | 1,446,000 | 0
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 5,000 | 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 | 1,446,000 | 0
Securities available for sale, continuous unrealized loss position, unrealized loss | $ 5,000 | $ 0

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- Definition Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for twelve months or longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563 + Details
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- Definition Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale in a continuous loss position. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563 + Details
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