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Note 2 - Securities (Details) - Securities in a Continuous Loss Position - USD ($) | Sep. 30, 2015 | Dec. 31, 2014
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Note 2 - Securities (Details) - Securities in a Continuous Loss Position [Line Items] |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | $ 17,825,000 | $ 190,579,000
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 127,000 | 740,000
Securities available for sale, continuous unrealized loss position, 12 months or more | 96,710,000 | 74,120,000
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 2,216,000 | 2,836,000
Securities available for sale, continuous unrealized loss position | 114,535,000 | 264,699,000
Securities available for sale, continuous unrealized loss position, unrealized loss | 2,343,000 | 3,576,000
US Government Agencies Debt Securities [Member] |  |
Note 2 - Securities (Details) - Securities in a Continuous Loss Position [Line Items] |  |
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 | 70,896,000 | 74,120,000
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 1,957,000 | 2,836,000
Securities available for sale, continuous unrealized loss position | 70,896,000 | 156,011,000
Securities available for sale, continuous unrealized loss position, unrealized loss | 1,957,000 | 3,038,000
Collateralized Mortgage Backed Securities [Member] |  |
Note 2 - Securities (Details) - Securities in a Continuous Loss Position [Line Items] |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | 6,831,000 | 49,940,000
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 37,000 | 218,000
Securities available for sale, continuous unrealized loss position, 12 months or more | 19,943,000 | 0
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 114,000 | 0
Securities available for sale, continuous unrealized loss position | 26,774,000 | 49,940,000
Securities available for sale, continuous unrealized loss position, unrealized loss | 151,000 | 218,000
Municipal General Obligation Bonds [Member] |  |
Note 2 - Securities (Details) - Securities in a Continuous Loss Position [Line Items] |  |
Securities available for sale, continuous unrealized loss position, less than 12 months | 10,994,000 | 54,104,000
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 90,000 | 307,000
Securities available for sale, continuous unrealized loss position, 12 months or more | 5,064,000 | 0
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 144,000 | 0
Securities available for sale, continuous unrealized loss position | 16,058,000 | 54,104,000
Securities available for sale, continuous unrealized loss position, unrealized loss | 234,000 | 307,000
Municipal Revenue Bonds [Member] |  |
Note 2 - Securities (Details) - Securities in a Continuous Loss Position [Line Items] |  |
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 | 807,000 | 0
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 1,000 | 0
Securities available for sale, continuous unrealized loss position | 807,000 | 4,644,000
Securities available for sale, continuous unrealized loss position, unrealized loss | 1,000 | 13,000
Other Debt Obligations [Member] |  |
Note 2 - Securities (Details) - Securities in a Continuous Loss Position [Line Items] |  |
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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- 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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