Note 4 - Fair Value Measurements (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Equity Securities, FV-NI	$ 10,958,000	$ 29,494,000
Equity Securities without Readily Determinable Fair Value, Amount	$ 1,600,000	800,000
Length of Time Generally Receive New Appraisal on Foreclosed Properties (Month)	18 months
Mutual Fund [Member] | Fair Value, Inputs, Level 1 [Member]
Equity Securities, FV-NI	$ 6,600,000	5,200,000
Preferred Stock [Member] | Fair Value, Inputs, Level 2 [Member]
Equity Securities, FV-NI	$ 2,800,000	$ 2,900,000