Note 15 - Mortgage Banking Activities (Details Textual) $ in Thousands	Sep. 30, 2024 USD ($)	Dec. 31, 2023 USD ($)
Loan, Managed and Securitized or Asset-Backed Financing Arrangement, Principal Outstanding	$ 1,840,000	$ 1,930,000
Measurement Input, Discount Rate [Member] \| Minimum [Member]
Servicing Asset, Measurement Input	0.10	0.10
Measurement Input, Discount Rate [Member] \| Maximum [Member]
Servicing Asset, Measurement Input	0.13	0.13
Measurement Input, Prepayment Rate [Member] \| Minimum [Member]
Servicing Asset, Measurement Input	0.064	0.06
Measurement Input, Prepayment Rate [Member] \| Maximum [Member]
Servicing Asset, Measurement Input	0.112	0.111
Measurement Input, Default Rate [Member]
Servicing Asset, Measurement Input	0.006	0.006
Mortgage Servicing Rights [Member]
Servicing Asset at Fair Value, Amount	$ 23,000	$ 24,000
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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