Net Loss Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended	6 Months Ended
Jul. 31, 2020	Jul. 31, 2019	Jul. 31, 2020	Jul. 31, 2019
Numerator
Net loss	$ (261,322)	$ (100,872)	$ (566,901)	$ (256,301)
Denominator
Weighted-average common shares outstanding (in shares)	159,697	150,812	159,021	150,283
Less: Weighted-average unvested common shares subject to repurchase or forfeiture (in shares)	(745)	(506)	(780)	(560)
Weighted-average shares used to compute net loss per share, basic and diluted (in shares)	158,952	150,306	158,241	149,723
Net loss per share
Net loss per share, basic and diluted (in dollars per share)	$ (1.64)	$ (0.67)	$ (3.58)	$ (1.71)

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
-Topic 260
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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.

+ References

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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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