Note 9 - Shareholders' Equity, Redeemable Convertible Preferred Stock, Options and Warrants - Schedule of Warrant Activity (Details) - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Outstanding, warrants (in shares)	0	7,065,000
Outstanding, warrants, weighted average exercise price (in dollars per share)	$ 0	$ 0.11
Granted, warrants (in shares)	0	0
Granted, warrants, weighted average exercise price (in dollars per share)	$ 0	$ 0
Exercised, warrants (in shares)	0	(515,000)
Exercised, warrants, weighted average exercise price (in dollars per share)	$ 0	$ 0.12
Forfeited, warrants (in shares)	0	(6,550,000)
Forfeited, warrants, weighted average exercise price (in dollars per share)	$ 0	$ 0.11
Outstanding, warrants (in shares)	0	0
Outstanding, warrants, weighted average exercise price (in dollars per share)	$ 0	$ 0