Note 6 - Preferred Stock - Summary of Warrants Activity (Details) - $ / shares	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Warrants outstanding and exercisable (in shares)
Warrants outstanding and exercisable (in shares)	2,272,203
Series F Preferred Warrants [Member]
Warrants outstanding and exercisable (in shares)	32,750	0
Warrants outstanding and exercisable, exercise price (in dollars per share)	$ 975
Granted, warrants (in shares)		32,750
Granted, warrants, exercise price (in dollars per share)		$ 975
Exercised, warrants (in shares)	(1,648)
Exercised, warrants, exercise price (in dollars per share)	$ 975
Warrants outstanding and exercisable (in shares)	31,102	32,750
Warrants outstanding and exercisable, exercise price (in dollars per share)	$ 975	$ 975