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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 | Jun. 30, 2013 | Dec. 31, 2012
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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 | $ 205,948 | $ 189,815
US Treasury Securities [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Note 8 - Fair Value Measurements (Details) - Assets and Liabilities at Fair Value on Recurring Basis [Line Items] |  |
Available-for-sale Securities | 0 | 0
US Treasury 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 | 2,032 | 2,073
US Treasury Securities [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Note 8 - Fair Value Measurements (Details) - Assets and Liabilities at Fair Value on Recurring Basis [Line Items] |  |
Available-for-sale Securities | 0 | 0
US Treasury Securities [Member] |  |
Note 8 - Fair Value Measurements (Details) - Assets and Liabilities at Fair Value on Recurring Basis [Line Items] |  |
Available-for-sale Securities | 2,032 | 2,073
US Government Agencies [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Note 8 - Fair Value Measurements (Details) - Assets and Liabilities at Fair Value on Recurring Basis [Line Items] |  |
Available-for-sale Securities | 0 | 0
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 | 161,786 | 129,564
US Government Agencies [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Note 8 - Fair Value Measurements (Details) - Assets and Liabilities at Fair Value on Recurring Basis [Line Items] |  |
Available-for-sale Securities | 0 | 0
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 | 161,786 | 129,564
States and Political Subdivisions [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Note 8 - Fair Value Measurements (Details) - Assets and Liabilities at Fair Value on Recurring Basis [Line Items] |  |
Available-for-sale Securities | 0 | 0
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 | 27,887 | 36,779
States and Political Subdivisions [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Note 8 - Fair Value Measurements (Details) - Assets and Liabilities at Fair Value on Recurring Basis [Line Items] |  |
Available-for-sale Securities | 0 | 0
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 | 27,887 | 36,779
Mortgage-backed Securities [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Note 8 - Fair Value Measurements (Details) - Assets and Liabilities at Fair Value on Recurring Basis [Line Items] |  |
Available-for-sale Securities | 0 | 0
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 | 3,581 | 4,569
Mortgage-backed Securities [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Note 8 - Fair Value Measurements (Details) - Assets and Liabilities at Fair Value on Recurring Basis [Line Items] |  |
Available-for-sale Securities | 0 | 0
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 | 3,581 | 4,569
Corporate Securities [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Note 8 - Fair Value Measurements (Details) - Assets and Liabilities at Fair Value on Recurring Basis [Line Items] |  |
Available-for-sale Securities | 0 | 0
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 | 8,438 | 14,575
Corporate Securities [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Note 8 - Fair Value Measurements (Details) - Assets and Liabilities at Fair Value on Recurring Basis [Line Items] |  |
Available-for-sale Securities | 0 | 0
Corporate Securities [Member] |  |
Note 8 - Fair Value Measurements (Details) - Assets and Liabilities at Fair Value on Recurring Basis [Line Items] |  |
Available-for-sale Securities | 8,438 | 14,575
Other Securities [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Note 8 - Fair Value Measurements (Details) - Assets and Liabilities at Fair Value on Recurring Basis [Line Items] |  |
Available-for-sale Securities | 0 | 0
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 | 2,224 | 2,255
Other Securities [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Note 8 - Fair Value Measurements (Details) - Assets and Liabilities at Fair Value on Recurring Basis [Line Items] |  |
Available-for-sale Securities | 0 | 0
Other Securities [Member] |  |
Note 8 - Fair Value Measurements (Details) - Assets and Liabilities at Fair Value on Recurring Basis [Line Items] |  |
Available-for-sale Securities | 2,224 | 2,255
Fair Value, Inputs, Level 1 [Member] |  |
Note 8 - Fair Value Measurements (Details) - Assets and Liabilities at Fair Value on Recurring Basis [Line Items] |  |
Available-for-sale Securities | 0 | 0
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 | 205,948 | 189,815
Fair Value, Inputs, Level 3 [Member] |  |
Note 8 - Fair Value Measurements (Details) - Assets and Liabilities at Fair Value on Recurring Basis [Line Items] |  |
Available-for-sale Securities | $ 0 | $ 0

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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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