Note 6 - Stockholders' Equity and Stock-based Compensation - Summary of Market-based Option Activity (Details) - Market-based Options [Member] - $ / shares	3 Months Ended	12 Months Ended
	Mar. 31, 2024	Dec. 31, 2023
Options balances, number of shares (in shares)	2,100,000
Options balances, weighted average exercise price (in dollars per share)	$ 6.78
Options balances, weighted average remaining life (Year)	9 years 2 months 19 days	9 years 5 months 8 days
Options granted, number of shares (in shares)	100,000
Options granted, weighted average exercise price (in dollars per share)	$ 9.32
Options exercised, number of shares (in shares)	0
Options exercised, weighted average exercise price (in dollars per share)	$ 0
Options canceled, number of shares (in shares)	0
Options canceled, weighted average exercise price (in dollars per share)	$ 0
Options expired, number of shares (in shares)	0
Options expired, weighted average exercise price (in dollars per share)	$ 0
Options balances, number of shares (in shares)	2,200,000	2,100,000
Options balances, weighted average exercise price (in dollars per share)	$ 6.89	$ 6.78
Options exercisable, number of shares (in shares)	0
Options exercisable, weighted average exercise price (in dollars per share)	$ 0