Note 4 - Mortgage Servicing Rights - Valuation Assumptions (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2025	Dec. 31, 2024
Aggregate portfolio principal balance	$ 1,640,000
Mortgage Servicing Rights [Member]
Aggregate portfolio principal balance	$ 1,639,890	$ 1,632,141
Weighted average rate of loans in MSRs portfolio	4.40%	4.20%
Fair value MSRs	$ 21,691	$ 21,043
Weighted average life in years (Year)	7 years 9 months 18 days	7 years 10 months 24 days
Weighted average constant prepayment rate	8.30%	8.30%
Decline in fair value from 10% adverse change (prepayment-only)	$ 715	$ 408
Decline in fair value from 20% adverse change (prepayment-only)	$ 1,075	$ 776
Effective discount rate	9.10%	10.20%
Decline in fair value from 10% adverse change (prepayment + discount rate)	$ 901	$ 911
Decline in fair value from 20% adverse change (prepayment + discount rate)	$ 1,733	$ 1,819

The face amount of financial assets, which are not recognized in the financial statements (off-balance sheet) because they fail to meet some other criterion for recognition.

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The hypothetical financial impact of a 10 percent adverse change of the discount rate on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date.

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Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

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Discount rate used to estimate the fair value of servicing assets and servicing liabilities.

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Estimated rate of prepayments of principal on servicing assets and servicing liabilities.

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Weighted average life of financial assets and financial liabilities, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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