Note 9 - Stock-Based Compensation - Schedule of Stock Options (Details) - $ / shares	9 Months Ended	12 Months Ended
	Sep. 30, 2025	Dec. 31, 2024
Outstanding, shares (in shares)	5,000
Outstanding, weighted average exercise price (in dollars per share)	$ 27.57
Outstanding, weighted average remaining contractual term (Year)	8 years 3 months 18 days	4 years 1 month 6 days
Granted, shares (in shares)	25,000
Granted, weighted average exercise price (in dollars per share)	$ 1.26
Outstanding, shares (in shares)	30,000	5,000
Outstanding, weighted average exercise price (in dollars per share)	$ 5.99	$ 27.57
Vested and expected to vest, shares (in shares)	30,000
Vested and expected to vest, weighted average exercise price (in dollars per share)	$ 5.99
Vested and expected to vest, weighted average remaining contractual term (Year)	8 years 3 months 18 days
Exercisable, shares (in shares)	5,000
Exercisable, weighted average exercise price (in dollars per share)	$ 27.57
Exercisable, weighted average remaining contractual term (Year)	3 years 4 months 24 days