Note 5 - Mortgage Loan Servicing (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Continuing Involvement with Transferred Financial Assets Custodial Escrow Balance	$ 12,100	$ 11,800
Valuation Allowance for Impairment of Recognized Servicing Assets, Balance, Ending Balance	0	0
Servicing Asset at Fair Value, Amount, Ending Balance	$ 15,400	$ 10,000
Servicing Assets and Servicing Liabilities at Fair Value, Assumptions Used to Estimate Fair Value, Discount Rate	8.00%	7.75%
Servicing Assets and Servicing Liabilities at Fair Value, Assumptions Used to Estimate Fair Value, Prepayment Speed	7.40%	14.00%
Servicing Assets and Servicing Liabilities at Fair Value, Assumptions Used to Estimate Fair Value, Expected Credit Losses	0.25%	0.40%
Servicing Assets and Servicing Liabilities at Fair Value, Assumptions Used to Estimate Fair Value, Weighted Average Life (Year)	8 years 6 months	6 years 1 month 6 days