Note 2 - Basis of Presentation and Significant Accounting Policies - Schedule of Antidilutive Securities Excluded From Computation of Earnings Per Share (Details)	3 Months Ended
	Mar. 31, 2022 shares
Antidilutive securities excluded from computation of earnings per share, amount (in shares)	3,629,760
Convertible Preferred Stock [Member]
Antidilutive securities excluded from computation of earnings per share, amount (in shares)	0
Convertible Preferred Stock Warrants [Member]
Antidilutive securities excluded from computation of earnings per share, amount (in shares)	0
Common Stock Warrants [Member]
Antidilutive securities excluded from computation of earnings per share, amount (in shares)	331,580
Share-Based Payment Arrangement, Option [Member]
Antidilutive securities excluded from computation of earnings per share, amount (in shares)	3,298,180