Note 10 - Stock-based Compensation - Stock-based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Unrecognized compensation expense	$ 9,766	$ 14,199
Expected weighted average period to be recognized (Year)	4 years 3 months 18 days	4 years 3 months 18 days
Share-Based Payment Arrangement, Option [Member]
Unrecognized compensation expense	$ 0	$ 0
Restricted Stock Units (RSUs) [Member]
Unrecognized compensation expense	$ 2,231	$ 4,977
Expected weighted average period to be recognized (Year)	2 years 3 months 18 days	2 years 2 months 12 days
Phantom Share Units (PSUs) [Member]
Unrecognized compensation expense	$ 7,535	$ 9,222
Expected weighted average period to be recognized (Year)	2 years	2 years 1 month 6 days