Note 9 - Stock-based Compensation - Schedule of Stock Options (Details) - $ / shares shares in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2026	Dec. 31, 2025
Outstanding, shares (in shares)	6,086
Outstanding, weighted average exercise price (in dollars per share)	$ 29.84
Outstanding, weighted average remaining contractual term (Year)	8 years 3 months 18 days	8 years 4 months 24 days
Granted, shares (in shares)	2,500
Granted, weighted average exercise price (in dollars per share)	$ 3.45
Expired, shares (in shares)	(398)
Expired, weighted average exercise price (in dollars per share)	$ 107.01
Outstanding, shares (in shares)	8,188	6,086
Outstanding, weighted average exercise price (in dollars per share)	$ 18.03	$ 29.84
Vested and expected to vest, shares (in shares)	8,188
Vested and expected to vest, weighted average exercise price (in dollars per share)	$ 18.03
Vested and expected to vest, weighted average remaining contractual term (Year)	8 years 3 months 18 days
Exercisable, shares (in shares)	5,688
Exercisable, weighted average exercise price (in dollars per share)	$ 24.44
Exercisable, weighted average remaining contractual term (Year)	7 years 9 months 18 days