Note 4 - Balance Sheet Components - Intangible assets (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Intangible assets, gross	$ 22,180	$ 22,180
Less: accumulated amortization	(6,386)	(5,087)
Intangible assets, net	15,794	17,093
Purchased Technology [Member]
Intangible assets, gross	22,100	22,100
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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-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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