Note 13 - Stock Plans and Stock-based Compensation -Schedule of Stock Option Activity (Details) - $ / shares	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Options outstanding, shares (in shares)	6,301,500	6,301,500
Options outstanding, weighted average exercise price (in dollars per share)	$ 0.06	$ 0.06
Options outstanding, weighted average fair value (in dollars per share)	$ 0.06	$ 0.06
Options outstanding, weighted average remaining contractual life (Year)	2 years 11 months 23 days	3 years 11 months 23 days
Options exerciseable, shares (in shares)	6,301,500	6,301,500
Options exercisable, weighted average exercise price (in dollars per share)	$ 0.06	$ 0.06
Options exercisable, weighted average fair value (in dollars per share)	$ 0.06	$ 0.06
Options exercisable, weighted average remaining contractual life (Year)	2 years 11 months 23 days	3 years 11 months 23 days