Note 8 - Equity Incentive Plans and Equity - Stock Options Activity (Details) - Service Period Stock Options [Member] $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2021 USD ($) $ / shares shares
Balance (in shares) | shares	1,327
Balance, weighted average exercise price (in dollars per share) | $ / shares	$ 45.88
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in shares) | shares	30
Granted, weighted average exercise price (in dollars per share) | $ / shares	$ 155.60
Exercised (in shares) | shares	(70)
Exercised, weighted average exercise price (in dollars per share) | $ / shares	$ 10.89
Forfeited (in shares) | shares	0
Forfeited, weighted average exercise price (in dollars per share) | $ / shares	$ 0
Balance (in shares) | shares	1,287
Balance, weighted average exercise price (in dollars per share) | $ / shares	$ 50.37
Balance, average remaining contractual term (Year)	6 years 2 months 26 days
Balance, aggregate intrinsic value | $	$ 73,719
Exercisable (in shares) | shares	924
Exercisable, weighted average exercise price (in dollars per share) | $ / shares	$ 22.30
Exercisable, average remaining contractual term (Year)	5 years 3 months 7 days
Exercisable, aggregate intrinsic value | $	$ 71,047