Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ References

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- Definition

The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

+ References

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-Publisher FASB
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Balance Sheet Components - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Oct. 31, 2019	Oct. 31, 2018	Oct. 31, 2019	Oct. 31, 2018
Finite-Lived Intangible Assets [Line Items]
Depreciation and amortization	$ 20.6	$ 16.9	$ 49.8	$ 60.3
Intangible assets amortization expense	$ 2.6	$ 0.9	$ 6.5	$ 1.6
Technology patents
Finite-Lived Intangible Assets [Line Items]
Useful Life (in years)			4 years
Developed technology
Finite-Lived Intangible Assets [Line Items]
Useful Life (in years)			6 years 2 months 12 days