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Note 9 - Hedging Activities (Details) - USD ($) | 1 Months Ended |  |  |  |
--- | --- | --- | --- | --- | ---
Jan. 31, 2016 | Feb. 29, 2012 | Mar. 31, 2016 | Jan. 26, 2016 | Jan. 25, 2016 | Dec. 31, 2015
Note 9 - Hedging Activities (Details) [Line Items] |  |  |  |  |  |
Junior Subordinated Debenture Owed to Unconsolidated Subsidiary Trust |  | $ 32,000,000 | $ 44,324,000 |  |  | $ 55,154,000
Fair Value of Interest Rate Swap Agreement Liability |  |  | $ 300,000 |  |  | $ 300,000
London Interbank Offered Rate (LIBOR) [Member] | Junior Subordinated Debt [Member] |  |  |  |  |  |
Note 9 - Hedging Activities (Details) [Line Items] |  |  |  |  |  |
Debt Instrument, Basis Spread on Variable Rate |  | 2.18% |  |  |  |
Derivative, Notional Amount |  | $ 32,000,000 |  | $ 21,000,000 | $ 32,000,000 |
Debt Instrument, Repurchased Face Amount |  |  |  | $ 11,000,000 |  |
Interest Expense, Debt | $ 200,000 |  |  |  |  |
Debt Instrument, Repurchase Amount | $ 11,000,000 |  |  |  |  |

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- Definition Aggregate notional amount specified by the derivative(s). Expressed as an absolute value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 12 -Section 13 -Sentence Column B + Details
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- Definition Amount of the cost of borrowed funds accounted for as interest expense for debt. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.8) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 + Details
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- Definition Including the current and noncurrent portions, the carrying value of junior subordinated long-term debt owed to unconsolidated subsidiary trusts as of the balance sheet date. Such debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets and was initially scheduled to be repaid after one year or beyond the normal operating cycle if longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.16) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.16) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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