Note 15 - Mortgage Banking Activities (Details Textual) $ in Thousands	Mar. 31, 2026 USD ($)	Dec. 31, 2025 USD ($)
Loan, Managed and Securitized or Asset-Backed Financing Arrangement, Principal Outstanding	$ 1,710,000	$ 1,730,000
Measurement Input, Discount Rate [Member] \| Minimum [Member]
Servicing Asset, Measurement Input	0.095	0.095
Measurement Input, Discount Rate [Member] \| Maximum [Member]
Servicing Asset, Measurement Input	0.125	0.125
Measurement Input, Prepayment Rate [Member] \| Minimum [Member]
Servicing Asset, Measurement Input	0.075	0.068
Measurement Input, Prepayment Rate [Member] \| Maximum [Member]
Servicing Asset, Measurement Input	0.102	0.118
Measurement Input, Default Rate [Member]
Servicing Asset, Measurement Input	0.006	0.005
Mortgage Servicing Rights [Member]
Mortgage servicing rights	$ 23,000	$ 22,000
Valuation Allowance for Impairment of Recognized Servicing Assets, Balance	$ 0	$ 0

This is the sum of principal amount outstanding for both securitized and unsecuritized loans of all types.

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