Note 7 - Loans and Allowance for Credit Losses on Loans (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Accrued Interest and Fees Receivable on Loans	$ 14,100,000	$ 10,400,000
Financing Receivable, Unamortized Loan Cost (Fee)	$ 5,600,000	4,600,000
Number of Days Past Due When Loans are Placed on Nonaccrual Status (Day)	90 days
Financing Receivable, Modified, Commitment to Lend	$ 0
Financing Receivable Troubled Debt Restructuring Individually Evaluated for Impairment Minimum		$ 500,000
Threshold Period Past Due for Loans to be Default (Day)	30 days	30 days
Loan Review Aggregate Exposure Amount on Nonhomogeneous Commercial Loan Relationships	$ 5,000,000
Concentrations of Loans to Any Single Industry in Excess of 10% of Total Loans	0	$ 0
Loans and Leases Receivable, Related Parties	39,196,000	49,309,000	$ 53,212,000
Loans Collectively Evaluated Fully Guaranteed or Cash Secured Loans	9,200,000	8,500,000
Financing Receivable, Collectively Evaluated for Impairment, Allowance for Credit Loss, Fully Guaranteed or Cash Secured Loans	0	$ 0
Minimum [Member]
Residential 1-4 Family Rental Small Loan / Large Loan Classification	600,000
Minimum [Member] | Any One Related Party [Member]
Loans and Leases Receivable, Related Parties	60,000
Maximum [Member]
Residential 1-4 Family Rental Small Loan / Large Loan Classification	$ 600,000