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Note 5 - Securities (Details) - Held to Maturity Securities (USD $) In Thousands, unless otherwise specified | Sep. 30, 2014 | Dec. 31, 2013
--- | --- | ---
Held to Maturity: |  |
Amortized Costs | $ 162,457 | $ 163,983
Gross Unrealized Gains | 6,826 | 3,304
Gross Unrealized Losses | 1,874 | 7,950
Fair Values | 167,409 | 159,337
US Government Agencies [Member] |  |
Held to Maturity: |  |
Amortized Costs | 18,928 | 13,973
Gross Unrealized Gains | 307 | 280
Gross Unrealized Losses | 666 | 1,448
Fair Values | 18,569 | 12,805
States And Political Subdivisions [Member] |  |
Held to Maturity: |  |
Amortized Costs | 141,683 | 149,490
Gross Unrealized Gains | 6,465 | 2,971
Gross Unrealized Losses | 1,206 | 6,502
Fair Values | 146,942 | 145,959
Mortgage-backed Securities [Member] |  |
Held to Maturity: |  |
Amortized Costs | 434 | 520
Gross Unrealized Gains | 52 | 53
Fair Values | 486 | 573
Corporate Securities [Member] |  |
Held to Maturity: |  |
Amortized Costs | 1,412 |
Gross Unrealized Gains | 2 |
Gross Unrealized Losses | 2 |
Fair Values | $ 1,412 |

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- Definition Amount of accumulated unrealized gain on investments in debt securities classified as held-to-maturity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 + Details
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- Definition Amount of accumulated unrealized loss on investments in debt securities classified as held-to-maturity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 + Details
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- Definition Amount before other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity. + References No definition available. + Details
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- Definition Fair value of investments in debt securities classified as held-to-maturity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 + Details
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