Aggregate notional amount, at origination, specified by the derivative(s). Expressed as an absolute value.

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Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

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Outstanding notional amount specified by the derivative(s). Expressed as an absolute value.

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Represents the amount of negative fair value.

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Net accrued on interest rate swaps.

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Notional Amount Of Option Contract

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Represents the fair value of open option contracts.

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Represents the amount of the positive fair value.

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Sum of Spot and Forward Contract Notional Amount

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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.

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The average percentage points added to the reference rate to compute the variable rate on the group of interest rate derivatives.

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Average fixed interest rate related to the group of interest rate derivatives.

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Average variable interest rate related to the group of interest rate derivatives.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of long-term debt (with maturities initially due after one year or beyond the operating cycle if longer) identified as Junior Subordinated Notes, which have a lower priority than senior instruments.

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Amount after tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Note 15 - Financial Derivatives (Details Textual) - USD ($)		3 Months Ended
	May 31, 2014	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Junior Subordinated Notes, Total	$ 119,100,000
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax		$ 2,193,000	$ 299,000
Cash [Member]
Collateral Already Posted, Aggregate Fair Value		1,300,000		$ 4,500,000
Interest Rate Swap [Member] \| Cash Flow Hedging [Member] \| Designated as Hedging Instrument [Member]
Derivative Outstanding, Notional Amount	$ 119,100,000	119,100,000
Derivative Original Maturity	10 years
Derivative, Average Fixed Interest Rate	2.61%
Derivative, Average Variable Interest Rate	2.17%
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax		428,000	(1,900,000)
Net Accrued on Interest Rate Swaps		274,000	479,000
Interest Rate Swap [Member] \| Fair Value Hedging [Member] \| Designated as Hedging Instrument [Member]
Derivative Outstanding, Notional Amount		$ 561,900,000	424,200,000
Derivative, Average Fixed Interest Rate		4.60%
Derivative, Average Variable Interest Rate		4.50%
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax		$ 11,100,000	1,900,000
Net Accrued on Interest Rate Swaps		229,000	$ 713,000
Derivative, Notional Amount at Origination		$ 561,900,000
Derivative, Average Basis Spread on Variable Rate		2.79%
Interest Rate Swap [Member] \| Fair Value Hedging [Member] \| Designated as Hedging Instrument [Member] \| Minimum [Member]
Derivative Original Maturity		2 years
Interest Rate Swap [Member] \| Fair Value Hedging [Member] \| Designated as Hedging Instrument [Member] \| Maximum [Member]
Derivative Original Maturity		10 years
Negative Fair Value [Member]
Notional Amount Of Option Contract		$ 1,000,000		1,000,000
Open Option Contracts Fair Value		3,000		9,000
Sum Of Spot And Forward Contract Notional Amount		57,600,000		32,100,000
Negative Fair Value		924,000		453,000
Positive Fair Value [Member]
Sum Of Spot And Forward Contract Notional Amount		78,000,000		108,500,000
Positive Fair Value		$ 1,500,000		$ 1,800,000