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Note 18 - Fair Value Measurements - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) | Dec. 31, 2016 | Dec. 31, 2015
--- | --- | ---
Available-for-sale Securities | $ 328,060,000 | $ 346,992,000
Fair Value, Inputs, Level 1 [Member] |  |
Available-for-sale Securities | 0 |
US Government Agencies Debt Securities [Member] |  |
Available-for-sale Securities | 152,040,000 | 147,040,000
Collateralized Mortgage Backed Securities [Member] |  |
Available-for-sale Securities | 47,392,000 | 67,074,000
Municipal General Obligation Bonds [Member] |  |
Available-for-sale Securities | 119,047,000 | 122,023,000
Municipal Revenue Bonds [Member] |  |
Available-for-sale Securities | 7,631,000 | 8,914,000
Other Debt Obligations [Member] |  |
Available-for-sale Securities | 1,950,000 | 1,941,000
Fair Value, Measurements, Recurring [Member] |  |
Total | 327,976,000 | 346,739,000
Fair Value, Measurements, Recurring [Member] | Interest Rate Swap [Member] |  |
Interest rate swap agreement | (84,000) | (253,000)
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Total | 0 | 0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Interest Rate Swap [Member] |  |
Interest rate swap agreement | 0 | 0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Total | 321,577,000 | 338,320,000
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Interest Rate Swap [Member] |  |
Interest rate swap agreement | (84,000) | (253,000)
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Total | 6,399,000 | 8,419,000
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Interest Rate Swap [Member] |  |
Interest rate swap agreement | 0 | 0
Fair Value, Measurements, Recurring [Member] | US Government Agencies Debt Securities [Member] |  |
Available-for-sale Securities | 152,040,000 | 147,040,000
Fair Value, Measurements, Recurring [Member] | US Government Agencies Debt Securities [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Available-for-sale Securities | 0 | 0
Fair Value, Measurements, Recurring [Member] | US Government Agencies Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Available-for-sale Securities | 152,040,000 | 147,040,000
Fair Value, Measurements, Recurring [Member] | US Government Agencies Debt Securities [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Available-for-sale Securities | 0 | 0
Fair Value, Measurements, Recurring [Member] | Collateralized Mortgage Backed Securities [Member] |  |
Available-for-sale Securities | 47,392,000 | 67,074,000
Fair Value, Measurements, Recurring [Member] | Collateralized Mortgage Backed Securities [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Available-for-sale Securities | 0 | 0
Fair Value, Measurements, Recurring [Member] | Collateralized Mortgage Backed Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Available-for-sale Securities | 47,392,000 | 67,074,000
Fair Value, Measurements, Recurring [Member] | Collateralized Mortgage Backed Securities [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Available-for-sale Securities | 0 | 0
Fair Value, Measurements, Recurring [Member] | Municipal General Obligation Bonds [Member] |  |
Available-for-sale Securities | 119,047,000 | 122,023,000
Fair Value, Measurements, Recurring [Member] | Municipal General Obligation Bonds [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Available-for-sale Securities | 0 | 0
Fair Value, Measurements, Recurring [Member] | Municipal General Obligation Bonds [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Available-for-sale Securities | 112,648,000 | 113,604,000
Fair Value, Measurements, Recurring [Member] | Municipal General Obligation Bonds [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Available-for-sale Securities | 6,399,000 | 8,419,000
Fair Value, Measurements, Recurring [Member] | Municipal Revenue Bonds [Member] |  |
Available-for-sale Securities | 7,631,000 | 8,914,000
Fair Value, Measurements, Recurring [Member] | Municipal Revenue Bonds [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Available-for-sale Securities | 0 | 0
Fair Value, Measurements, Recurring [Member] | Municipal Revenue Bonds [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Available-for-sale Securities | 7,631,000 | 8,914,000
Fair Value, Measurements, Recurring [Member] | Municipal Revenue Bonds [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Available-for-sale Securities | 0 | 0
Fair Value, Measurements, Recurring [Member] | Other Debt Obligations [Member] |  |
Available-for-sale Securities | 1,950,000 | 1,941,000
Fair Value, Measurements, Recurring [Member] | Other Debt Obligations [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Available-for-sale Securities | 0 | 0
Fair Value, Measurements, Recurring [Member] | Other Debt Obligations [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Available-for-sale Securities | 1,950,000 | 1,941,000
Fair Value, Measurements, Recurring [Member] | Other Debt Obligations [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Available-for-sale Securities | $ 0 | $ 0

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- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258 + Details
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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=65884222&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=73527792&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=66010992&loc=d3e26610-111562 + Details
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