Consolidated Balance Sheets (Parentheticals) - USD ($)	Dec. 31, 2023	Dec. 31, 2022
Allowance for doubtful accounts	$ 10,000	$ 10,000
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	100,000,000	100,000,000
Common stock, shares issued (in shares)	75,881,840	69,306,497
Common stock, shares outstanding (in shares)	75,848,507	69,273,164
Treasury stock, shares (in shares)	33,333	33,333