Note 11 - Stockholders' Equity (Deficit) - Stock-based Compensation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Share-based Payment Arrangement, Expense	$ 11,826	$ 32,633	$ 36,575
Selling, General and Administrative Expenses [Member]
Share-based Payment Arrangement, Expense	0	13,587	0
Selling, General and Administrative Expenses [Member] | Share-Based Payment Arrangement, Option [Member]
Share-based Payment Arrangement, Expense	2,993	3,873	3,937
Selling, General and Administrative Expenses [Member] | Restricted Stock Units (RSUs) [Member]
Share-based Payment Arrangement, Expense	5,054	8,239	13,841
Research and Development Expense [Member] | Share-Based Payment Arrangement, Option [Member]
Share-based Payment Arrangement, Expense	553	573	3,018
Research and Development Expense [Member] | Restricted Stock Units (RSUs) [Member]
Share-based Payment Arrangement, Expense	$ 3,227	$ 6,361	$ 15,779