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Note 2 - Securities (Details) - Securities in a Continuous Loss Position - USD ($) | Mar. 31, 2016 | Dec. 31, 2015
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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 | $ 18,042,000 | $ 21,452,000
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 172,000 | 78,000
Securities available for sale, continuous unrealized loss position, 12 months or more | 70,328,000 | 142,424,000
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 667,000 | 1,991,000
Securities available for sale, continuous unrealized loss position | 88,370,000 | 163,876,000
Securities available for sale, continuous unrealized loss position, unrealized loss | 839,000 | 2,069,000
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 | 7,046,000 | 0
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 114,000 | 0
Securities available for sale, continuous unrealized loss position, 12 months or more | 42,601,000 | 76,496,000
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 466,000 | 1,552,000
Securities available for sale, continuous unrealized loss position | 49,647,000 | 76,496,000
Securities available for sale, continuous unrealized loss position, unrealized loss | 580,000 | 1,552,000
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 | 7,942,000 | 18,025,000
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 36,000 | 69,000
Securities available for sale, continuous unrealized loss position, 12 months or more | 17,055,000 | 34,660,000
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 75,000 | 235,000
Securities available for sale, continuous unrealized loss position | 24,997,000 | 52,685,000
Securities available for sale, continuous unrealized loss position, unrealized loss | 111,000 | 304,000
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 | 3,054,000 | 1,981,000
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 22,000 | 4,000
Securities available for sale, continuous unrealized loss position, 12 months or more | 10,551,000 | 30,134,000
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 126,000 | 201,000
Securities available for sale, continuous unrealized loss position | 13,605,000 | 32,115,000
Securities available for sale, continuous unrealized loss position, unrealized loss | 148,000 | 205,000
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 | 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 | 121,000 | 1,134,000
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss | 1,000 | 3,000
Securities available for sale, continuous unrealized loss position | 121,000 | 1,134,000
Securities available for sale, continuous unrealized loss position, unrealized loss | 1,000 | 3,000
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 | 1,446,000
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss | 0 | 5,000
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 | 1,446,000
Securities available for sale, continuous unrealized loss position, unrealized loss | $ 0 | $ 5,000

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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=73527792&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=73527792&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=73527792&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=73527792&loc=d3e27290-111563 + Details
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