Note 2 - Accounts Receivable - Accounts Receivable (Details) - USD ($)	Dec. 31, 2023	Dec. 31, 2022
Accounts receivable - current	$ 2,177,813	$ 1,930,488
Less allowance for credit losses	(68,620)	(62,000)
Accounts receivable current - net	2,109,193	1,868,488
Accounts receivable - long-term	$ 891,351	$ 1,523,793