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Note 11 - Fair Values - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) | Sep. 30, 2016 | Dec. 31, 2015
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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 | 137,883,000 | 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] | US Government Agencies Debt Securities [Member] |  |
Available-for-sale Securities | 137,883,000 | 147,040,000
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 | 52,569,000 | 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] | Collateralized Mortgage Backed Securities [Member] |  |
Available-for-sale Securities | 52,569,000 | 67,074,000
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 | 118,017,000 | 113,604,000
Fair Value, Measurements, Recurring [Member] | Municipal General Obligation Bonds [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Available-for-sale Securities | 6,469,000 | 8,419,000
Fair Value, Measurements, Recurring [Member] | Municipal General Obligation Bonds [Member] |  |
Available-for-sale Securities | 124,486,000 | 122,023,000
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 | 8,518,000 | 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] | Municipal Revenue Bonds [Member] |  |
Available-for-sale Securities | 8,518,000 | 8,914,000
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 | 1,987,000 | 1,941,000
Fair Value, Measurements, Recurring [Member] | Other Debt Obligations [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Available-for-sale Securities | 0 | 0
Fair Value, Measurements, Recurring [Member] | Other Debt Obligations [Member] |  |
Available-for-sale Securities | 1,987,000 | 1,941,000
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Interest Rate Swap [Member] |  |
Interest rate swap | 0 | 0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Total | 0 | 0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Interest Rate Swap [Member] |  |
Interest rate swap | (165,000) | (253,000)
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Total | 318,809,000 | 338,320,000
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Interest Rate Swap [Member] |  |
Interest rate swap | 0 | 0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Total | 6,469,000 | 8,419,000
Fair Value, Measurements, Recurring [Member] | Interest Rate Swap [Member] |  |
Interest rate swap | (165,000) | (253,000)
Fair Value, Measurements, Recurring [Member] |  |
Total | 325,278,000 | 346,739,000
US Government Agencies Debt Securities [Member] |  |
Available-for-sale Securities | 137,883,000 | 147,040,000
Collateralized Mortgage Backed Securities [Member] |  |
Available-for-sale Securities | 52,569,000 | 67,074,000
Municipal General Obligation Bonds [Member] |  |
Available-for-sale Securities | 124,486,000 | 122,023,000
Municipal Revenue Bonds [Member] |  |
Available-for-sale Securities | 8,518,000 | 8,914,000
Other Debt Obligations [Member] |  |
Available-for-sale Securities | 1,987,000 | 1,941,000
Fair Value, Inputs, Level 1 [Member] |  |
Available-for-sale Securities | 0 |
Available-for-sale Securities | $ 325,443,000 | $ 346,992,000

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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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- Definition Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958 + Details
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