Note 7 - Loans and Allowance for Credit Losses on Loans - Financial Effect of Modifications (Details)	12 Months Ended
	Dec. 31, 2023
Commercial Loan [Member]
Weighted-average payment delay (Month)	0 months
Weighted-average term extension (Month)	12 months
Commercial Real Estate Owner Occupied, Other [Member]
Weighted-average payment delay (Month)	0 months
Weighted-average term extension (Month)	12 months
Commercial Real Estate Nonowner Occupied, Retail [Member]
Weighted-average payment delay (Month)	0 months
Weighted-average term extension (Month)	20 months
Residential 1-4 Family Real Estate, Personal Residence [Member]
Weighted-average payment delay (Month)	8 months
Weighted-average term extension (Month)	5 months
Residential 1-4 Family Real Estate, Rental Small Loan [Member]
Weighted-average payment delay (Month)	0 months
Weighted-average term extension (Month)	16 months