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Note 14 - Financial Derivatives (Details Textual) - USD ($) $ in Thousands		9 Months Ended	12 Months Ended
	May 31, 2014	Sep. 30, 2025	Dec. 31, 2022	Dec. 31, 2024
Junior Subordinated Notes, Total	$ 119,100
Derivative Asset, Statement of Financial Position [Extensible Enumeration]		Other Assets
Derivative Liability, Statement of Financial Position [Extensible Enumeration]		Other Liabilities
Interest Rate Swap [Member] | Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member]
Derivative Outstanding, Notional Amount	$ 119,100	$ 968,600		$ 680,500
Derivative, Notional Amount		26,300		32,700
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		0		0
Interest Rate Swap [Member] | Fair Value Hedging [Member] | Designated as Hedging Instrument [Member]
Derivative, Notional Amount		625,987		$ 875,117
Interest Rate Contract [Member] | Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member]
Derivative Outstanding, Notional Amount		48,100
Derivative, Notional Amount		1,800
Interest Rate Contract [Member] | Fair Value Hedging [Member] | Designated as Hedging Instrument [Member]
Derivative, Notional Amount		$ 626,000
Interest Rate Contract [Member] | Fair Value Hedging [Member] | Designated as Hedging Instrument [Member] | Minimum [Member]
Derivative, Term of Contract (Year)		3 years
Interest Rate Contract [Member] | Fair Value Hedging [Member] | Designated as Hedging Instrument [Member] | Maximum [Member]
Derivative, Term of Contract (Year)		10 years
Interest Rate Contract [Member] | Fair Value Hedging [Member] | Designated as Hedging Instrument [Member] | Central Counterparties (CCP) [Member]
Derivative, Notional Amount		$ 571,600
Derivative, Loss on Derivative		3,700
Loans Receivable with Partial-term Hedging Designation [Member]
Derivative, Notional Amount		4,400
Hedged Asset, Fair Value Hedge		577,900
Loan, Notional Amount		921,600
Derivative, Gain on Derivative		$ 5,200

X

- Definition

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

+ References

No definition available.

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- Definition

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+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

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- Definition

The notional amount of a loan.

+ References

No definition available.

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- Definition

Indicates line item in statement of financial position that includes derivative asset.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483444/210-20-55-10

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4A
-Subparagraph (b)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-4A

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- Definition

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-Name Accounting Standards Codification
-Section 55
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- Definition

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

+ References

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-Topic 815
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- Definition

Nominal or face amount used to calculate payment on derivative.

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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

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- Definition

Amount of asset hedged in fair value hedging relationship.

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X

- 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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Paragraph 1
-Subparagraph (SX 210.5-02(22))
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