Note 8 - Net Loss Per Share - Schedule of Antidilutive Securities (Details) - shares		3 Months Ended
		Mar. 31, 2026	Mar. 31, 2025
Convertible Series F Preferred Stock [Member]
Antidilutive securities (in shares)	[1]	46,783	52,512
Series F Preferred Warrants [Member]
Antidilutive securities (in shares)	[2]	8,097,347	2,784,921
Common Stock Warrants [Member]
Antidilutive securities (in shares)		2,102,467	2,262,203

[1] Calculation assumes conversion of the stated value and accrued dividends of the Series F Preferred Stock into Common Stock at a conversion price of $3.77 per share as of March 31, 2026, and a conversion price of $11.17 as of March 31, 2025.

[2] Calculation assumes exercise of the Preferred Warrants for cash into Series F Preferred Stock and subsequent conversion of the Series F Preferred Stock into Common Stock at a conversion price of $3.77 as of March 31, 2026, and a conversion price of $11.17 as of March 31, 2025.