Note 1 - Summary of Significant Accounting Policies - Premises and Equipment (Details)	Dec. 31, 2023
Building [Member] | Minimum [Member]
Useful life (Year)	37 years 6 months
Building [Member] | Maximum [Member]
Useful life (Year)	50 years
Furniture, Fixtures, and Equipment [Member] | Minimum [Member]
Useful life (Year)	3 years
Furniture, Fixtures, and Equipment [Member] | Maximum [Member]
Useful life (Year)	10 years
Software and Software Development Costs [Member]
Useful life (Year)	3 years
Automobiles [Member]
Useful life (Year)	5 years