Net Loss Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended	9 Months Ended
Oct. 31, 2020	Oct. 31, 2019	Oct. 31, 2020	Oct. 31, 2019
Numerator
Net loss	$ (201,531)	$ (57,639)	$ (768,432)	$ (313,940)
Denominator
Weighted-average common shares outstanding (in shares)	161,114	153,086	159,717	151,226
Less: Weighted-average unvested common shares subject to repurchase or forfeiture (in shares)	(599)	(682)	(719)	(567)
Weighted-average shares used to compute net loss per share, basic and diluted (in shares)	160,515	152,404	158,998	150,659
Net loss per share
Net loss per share, basic and diluted (in dollars per share)	$ (1.26)	$ (0.38)	$ (4.83)	$ (2.08)

The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or loss for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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-Name Accounting Standards Codification
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Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities; of income (loss) available to common shareholders.

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-Publisher FASB
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Average number of shares or units issued and outstanding that are used in calculating basic and diluted earnings per share (EPS).

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Number of shares of common stock subject to repurchase or cancellation determined by relating the portion of time within a reporting period that these shares have been outstanding to the total time in that period. Common stock subject to repurchase are outstanding common shares that are contingently returnable (that is, subject to recall).

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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