Note 14 - Financial Derivatives (Details Textual) $ in Thousands		12 Months Ended
May 31, 2014 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Junior Subordinated Notes, Total	$ 119,100	$ 119,136
Cash [Member]
Collateral Already Posted, Aggregate Fair Value		5,900	$ 11,900
Interest Rate Swap [Member]
Derivative, Notional Amount		324,800
Interest Rate Swap [Member] \| Cash Flow Hedging [Member] \| Designated as Hedging Instrument [Member]
Derivative Outstanding, Notional Amount	$ 119,100	457,000	83,200
Derivative Asset, Number of Instruments Held	5
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		$ 729,280	478,266
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		$ 748,600	44,700
Hedged Asset, Fair Value Hedge		404,400	25,000
Hedged Asset, Fair Value Hedge, Last-of-Layer, Cumulative Increase (Decrease)		$ 30	$ 342

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.

+ References

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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 number of derivative instruments of a particular derivative asset or group of derivative assets held by the entity.

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Nominal or face amount used to calculate payment on derivative.

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Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of asset hedged in fair value hedging relationship.

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Amount of cumulative increase (decrease) in fair value of hedged asset in fair value hedge, attributable to hedged risk, in last-of-layer hedging relationship.

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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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