Note 16 - Financial Derivatives (Details Textual) $ in Thousands		12 Months Ended
May 31, 2014 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Junior Subordinated Notes, Total	$ 119,100	$ 119,136	$ 119,136
Cash [Member]
Collateral Already Posted, Aggregate Fair Value		0	5,900
Interest Rate Swap [Member]
Derivative, Notional Amount		204,300
Interest Rate Swap [Member] \| Cash Flow Hedging [Member] \| Designated as Hedging Instrument [Member]
Derivative Outstanding, Notional Amount	$ 119,100	595,400	457,000
Derivative, Notional Amount		0	119,136
Derivative Asset, Number of Instruments Held	5
Derivative Original Maturity (Year)	10 years
Deferred Gain on Early Termination of Derivative		4,000
Interest Rate Swap [Member] \| Cash Flow Hedging [Member] \| Designated as Hedging Instrument [Member] \| Central Counterparties (CCP) [Member]
Derivative, Notional Amount		205,600
Derivative, Gain on Derivative		20,200
Interest Rate Swap [Member] \| Fair Value Hedging [Member] \| Designated as Hedging Instrument [Member]
Derivative, Notional Amount		$ 874,034	729,280
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
Interest Rate Swap [Member] \| Fair Value Hedging [Member] \| Designated as Hedging Instrument [Member] \| Central Counterparties (CCP) [Member]
Derivative, Notional Amount		$ 449,300
Derivative, Gain on Derivative		25,800
Loans Receivable with Partial-term Hedging Designation [Member]
Derivative, Notional Amount			748,600
Hedged Asset, Fair Value Hedge		669,700	404,400
Loan, Notational Amount		1,200
Hedged Asset, Fair Value Hedge, Last-of-Layer, Cumulative Increase (Decrease)		$ 31,000	$ 4,900

The amount of deferred gain on early termination of derivative recognized.

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

+ References

No definition available.

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

+ References

No definition available.

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The notational amount of a loan.

+ References

No definition available.

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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

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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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Amount of increase in the fair value of derivatives recognized in the income statement.

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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.

+ References

No definition available.

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- Definition

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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- Definition

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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