Note 5 - Loans and Allowance for Credit Losses (Details Textual) Pure in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Dec. 31, 2022 USD ($)
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease)	$ 1,500,000	$ 1,800,000
Off-Balance-Sheet, Credit Loss, Liability, Credit Loss Expense (Reversal)	144,000	28,000	$ 503,000	$ 162,000
Financing Receivable Number Of Loans 90 Days Past Due And Still Accruing	0		0		$ 0
Impaired Financing Receivable, Interest Income, Cash Basis Method	$ 0	$ 0	$ 0	$ 0
Number Of Loans Identified As Troubled Debt Restructurings	0		0		0
Financing Receivable, Modified, Commitment to Lend	$ 0		$ 0		$ 0
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts					0