Note 4 - Balance Sheet Components - Right-of-use Assets, Net (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Right-of-use assets, net	$ 12,237	$ 6,838
Facilities [Member]
Right-of-use assets, net	12,237	6,836
Office Equipment [Member]
Right-of-use assets, net	$ 0	$ 2