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Note 8 - Fair Value Measurements (Details) - Assets and Liabilities at Fair Value on Recurring Basis (USD $) In Thousands, unless otherwise specified | Sep. 30, 2014 | Dec. 31, 2013
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Note 8 - Fair Value Measurements (Details) - Assets and Liabilities at Fair Value on Recurring Basis [Line Items] |  |
Available-for-sale Securities Fair Value | $ 205,020 | $ 181,712
US Government Agencies [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Note 8 - Fair Value Measurements (Details) - Assets and Liabilities at Fair Value on Recurring Basis [Line Items] |  |
Available-for-sale Securities Fair Value | 174,444 | 147,854
US Government Agencies [Member] |  |
Note 8 - Fair Value Measurements (Details) - Assets and Liabilities at Fair Value on Recurring Basis [Line Items] |  |
Available-for-sale Securities Fair Value | 174,444 | 147,854
States And Political Subdivisions [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Note 8 - Fair Value Measurements (Details) - Assets and Liabilities at Fair Value on Recurring Basis [Line Items] |  |
Available-for-sale Securities Fair Value | 20,545 | 23,456
States And Political Subdivisions [Member] |  |
Note 8 - Fair Value Measurements (Details) - Assets and Liabilities at Fair Value on Recurring Basis [Line Items] |  |
Available-for-sale Securities Fair Value | 20,545 | 23,456
Mortgage-backed Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Note 8 - Fair Value Measurements (Details) - Assets and Liabilities at Fair Value on Recurring Basis [Line Items] |  |
Available-for-sale Securities Fair Value | 2,206 | 2,840
Mortgage-backed Securities [Member] |  |
Note 8 - Fair Value Measurements (Details) - Assets and Liabilities at Fair Value on Recurring Basis [Line Items] |  |
Available-for-sale Securities Fair Value | 2,206 | 2,840
Corporate Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Note 8 - Fair Value Measurements (Details) - Assets and Liabilities at Fair Value on Recurring Basis [Line Items] |  |
Available-for-sale Securities Fair Value | 7,692 | 7,395
Corporate Securities [Member] |  |
Note 8 - Fair Value Measurements (Details) - Assets and Liabilities at Fair Value on Recurring Basis [Line Items] |  |
Available-for-sale Securities Fair Value | 7,692 | 7,395
Other Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Note 8 - Fair Value Measurements (Details) - Assets and Liabilities at Fair Value on Recurring Basis [Line Items] |  |
Available-for-sale Securities Fair Value | 133 | 167
Other Securities [Member] |  |
Note 8 - Fair Value Measurements (Details) - Assets and Liabilities at Fair Value on Recurring Basis [Line Items] |  |
Available-for-sale Securities Fair Value | 133 | 167
Fair Value, Inputs, Level 2 [Member] |  |
Note 8 - Fair Value Measurements (Details) - Assets and Liabilities at Fair Value on Recurring Basis [Line Items] |  |
Available-for-sale Securities Fair Value | $ 205,020 | $ 181,712

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- Definition Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 2: 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 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26610-111562 + Details
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