Balance Sheet Components - Schedule of Intangible Assets, Net (Details) - USD ($) $ in Thousands	Apr. 30, 2017	Jan. 31, 2017
Finite Lived Intangible Assets [Line Items]
Intangible assets, net	$ 6,184	$ 6,560
Technology patents
Finite Lived Intangible Assets [Line Items]
Technology patents	10,125	10,125
Accumulated amortization	(3,941)	(3,565)
Intangible assets, net	$ 6,184	$ 6,560

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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

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