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Note 5 - Securities (Details) - Held to Maturity Securities (USD $) In Thousands, unless otherwise specified | 6 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2013 | Dec. 31, 2012
Held to Maturity: |  |
Amortized Costs | $ 166,915 | $ 160,539
Gross Unrealized Gains | 3,890 | 10,523
Gross Unrealized Losses | 6,921 | 216
Fair Values | 163,884 | 170,846
US Government Agencies [Member] |  |
Held to Maturity: |  |
Amortized Costs | 13,980 | 7,988
Gross Unrealized Gains | 336 | 563
Gross Unrealized Losses | 651 | 0
Fair Values | 13,665 | 8,551
Mortgage-backed Securities [Member] |  |
Held to Maturity: |  |
Amortized Costs | 586 | 691
Gross Unrealized Gains | 62 | 73
Gross Unrealized Losses | 0 | 0
Fair Values | 648 | 764
States and Political Subdivisions [Member] |  |
Held to Maturity: |  |
Amortized Costs | 152,349 | 151,209
Gross Unrealized Gains | 3,492 | 9,880
Gross Unrealized Losses | 6,270 | 216
Fair Values | 149,571 | 160,873
Corporate Securities [Member] |  |
Held to Maturity: |  |
Amortized Costs |  | 651
Gross Unrealized Gains |  | 7
Gross Unrealized Losses |  | 0
Fair Values |  | $ 658

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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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- Definition Amount of unrecognized gain before loss on investments in held-to-maturity securities. + 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 unrecognized loss before gain on investments in held-to-maturity securities. Excludes write-down for other than temporary impairment (OTTI). + 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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