Note 13 - Income Taxes - Components of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Net federal and state operating losses	$ 113,649	$ 159,939
Research and development credits	71,197	66,331
Royalty income	106,007	28,034
Stock-based compensation	14,512	10,732
Capitalized R&D	8,997
Leasing obligations	1,836	1,135
Other	4,809	5,563
Total deferred tax assets	321,007	271,734
Fixed assets	(607)	(124)
Right of use asset	(1,527)	(854)
Total deferred tax liabilities	(2,134)	(978)
Valuation allowance	(318,714)	$ (270,756)
Net deferred tax assets	$ 159