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Note 9 - Hedging Activities (Details Textual) - USD ($) | 1 Months Ended |  |  |  |
--- | --- | --- | --- | --- | ---
Jan. 26, 2016 | Feb. 29, 2012 | Sep. 30, 2018 | Dec. 31, 2017 | Jan. 31, 2016 | Jan. 25, 2016
Junior Subordinated Debenture Owed to Unconsolidated Subsidiary Trust, Total |  | $ 32,000,000 | $ 46,029,000 | $ 45,517,000 |  |
Fair Value of Interest Rate Swap Agreement Liability |  |  |  | $ 100,000 |  |
Interest Expense, Debt, Total | $ 200,000 |  |  |  |  |
Junior Subordinated Debt [Member] | London Interbank Offered Rate (LIBOR) [Member] |  |  |  |  |  |
Debt Instrument, Basis Spread on Variable Rate |  | 2.18% |  |  |  |
Derivative, Notional Amount | 21,000,000 | $ 32,000,000 |  |  |  | $ 32,000,000
Debt Instrument, Repurchased Face Amount | $ 11,000,000 |  |  |  |  |
Debt Instrument, Repurchase Amount |  |  |  |  | $ 11,000,000 |

X
- 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/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6036836-161870 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.8) -URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227 + 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://fasb.org/us-gaap/role/ref/legacyRef -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://fasb.org/us-gaap/role/ref/legacyRef -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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