Balance Sheet Components (Details) - Intangible assets - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Balance Sheet Components (Details) - Intangible assets [Line Items]
Intangible assets, gross	$ 24,080	$ 80
Less accumulated amortization	453	40
Intangible assets, net	23,627	40
Purchased Technology [Member]
Balance Sheet Components (Details) - Intangible assets [Line Items]
Intangible assets, gross	22,400
In Process Research and Development [Member]
Balance Sheet Components (Details) - Intangible assets [Line Items]
Intangible assets, gross	1,600
Intellectual Property [Member]
Balance Sheet Components (Details) - Intangible assets [Line Items]
Intangible assets, gross	$ 80	$ 80