Note 4 - Balance Sheet Components - Intangible Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Intangible assets, gross	$ 20,380	$ 20,380
Less: accumulated amortization	(6,318)	(5,019)
Intangible assets, net	14,062	15,361
Developed Technology Rights [Member]
Intangible assets, gross	20,300	20,300
Intellectual Property [Member]
Intangible assets, gross	$ 80	$ 80

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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-Publisher FASB
-Name Accounting Standards Codification
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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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-Publisher FASB
-Name Accounting Standards Codification
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