Note 3 - Accounts Receivable (Details Textual) - USD ($)	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Accounts Receivable, after Allowance for Credit Loss	$ 19,700,000	$ 21,900,000	$ 18,400,000
Accounts Receivable, Allowance for Credit Loss	$ 105,223	$ 143,631	$ 75,930