Balance Sheet Components - Intangible Assets, Net (Details) - USD ($) $ in Thousands	Oct. 31, 2019	Jan. 31, 2019
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 75,225	$ 27,825
Accumulated Amortization	(14,197)	(7,707)
Net Carrying Amount	61,028	20,118
Technology patents
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	19,125	10,125
Accumulated Amortization	(8,235)	(6,572)
Net Carrying Amount	10,890	3,553
Developed technology
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	56,100	17,700
Accumulated Amortization	(5,962)	(1,135)
Net Carrying Amount	$ 50,138	$ 16,565

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/disclosureRef
-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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 928
-SubTopic 340
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6473545&loc=d3e61844-108004

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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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-Name Accounting Standards Codification
-Topic 350
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