Note 3 - Investment Securities - Schedule of Held-to-maturity Investment Securities with Credit Rating (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss	$ 16,078	$ 17,275
Standard & Poor's, AAA Rating [Member]
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss	13,578	14,775
Not Rated - Non Agency [Member]
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss	2,500	2,500
Nontaxable Municipal Bonds [Member]
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss	13,578	14,775
Nontaxable Municipal Bonds [Member] \| Standard & Poor's, AAA Rating [Member]
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss	13,578	14,775
Nontaxable Municipal Bonds [Member] \| Not Rated - Non Agency [Member]
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss	0	0
Subordinated Debt [Member]
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss	2,500	2,500
Subordinated Debt [Member] \| Standard & Poor's, AAA Rating [Member]
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss	0	0
Subordinated Debt [Member] \| Not Rated - Non Agency [Member]
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss	$ 2,500	$ 2,500