Note 9 - Warrants - Summary of Outstanding Common Stock Purchase Warrants (Details)	Mar. 31, 2025 $ / shares shares
Exercisable, warrants (in shares) | shares	5,901
Exercisable, warrant, weighted average exercise price (in dollars per share) | $ / shares	$ 208.75
Warrants Expiring September 2023 [Member]
Exercisable, warrants (in shares) | shares	429
Exercisable, warrant, weighted average exercise price (in dollars per share) | $ / shares	$ 1,346.4
Warrants Expiring May 2024 [Member]
Exercisable, warrants (in shares) | shares	409
Exercisable, warrant, weighted average exercise price (in dollars per share) | $ / shares	$ 1,350
Warrants Expiring October 2024 [Member]
Exercisable, warrants (in shares) | shares	5,063
Exercisable, warrant, weighted average exercise price (in dollars per share) | $ / shares	$ 20.16