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Note 14 - Financial Derivatives (Details Textual) $ in Thousands |  | 12 Months Ended |
--- | --- | --- | ---
May 31, 2014 USD ($) | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($)
Junior Subordinated Notes, Total | $ 119,100 | $ 119,136 |
Cash [Member] |  |  |
Collateral Already Posted, Aggregate Fair Value |  | 11,900 | $ 7,100
Interest Rate Swap [Member] | Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] |  |  |
Derivative Asset, Number of Instruments Held | 5 |  |
Derivative Outstanding, Notional Amount | $ 119,100 |  |
Derivative Original Maturity (Year) | 10 years |  |
Derivative, Notional Amount |  | 119,136 | 119,136
Interest Rate Swap [Member] | Fair Value Hedging [Member] | Designated as Hedging Instrument [Member] |  |  |
Derivative, Notional Amount |  | $ 478,266 | $ 579,584
Interest Rate Swap [Member] | Fair Value Hedging [Member] | Designated as Hedging Instrument [Member] | Minimum [Member] |  |  |
Derivative, Term of Contract (Year) |  | 3 years |
Interest Rate Swap [Member] | Fair Value Hedging [Member] | Designated as Hedging Instrument [Member] | Maximum [Member] |  |  |
Derivative, Term of Contract (Year) |  | 10 years |
Loans Receivable with Partial-term Hedging Designation [Member] |  |  |
Derivative, Notional Amount |  | $ 44,700 |
Loans and Leases Receivable, Gross, Total |  | 25,000 |
Hedged Asset, Fair Value Hedge, Last-of-Layer, Amount |  | 25,000 |
Hedged Asset, Fair Value Hedge, Last-of-Layer, Cumulative Increase (Decrease) |  | $ 342 |

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- Definition The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4H -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5624258-113959 + Details
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- Definition Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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