Note 3 - Securities (Details Textual) $ in Millions	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Number of Non-government Securities of Any Individual Issuer Exceeding 10 Percent of Shareholders' Equity	0	0
Equity Securities without Readily Determinable Fair Value, Amount	$ 0.5	$ 0.5
Preferred Stock of Privately-held Bank Holding Company [Member]
Equity Securities without Readily Determinable Fair Value, Dividend Rate	8.25%
Preferred Stock of Privately-held Bank Holding Company [Member] | Other Assets [Member]
Equity Securities without Readily Determinable Fair Value, Amount	$ 0.5	$ 0.5