v3.20.4

Stockholders' Equity - Schedule of Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Jan. 31, 2021	Jan. 31, 2020	Jan. 31, 2019
Number of stock options outstanding
Outstanding at beginning of period (in shares)	8,425,000
Granted (in shares)	1,678,000		0
Exercised (in shares)	(3,602,000)
Canceled (in shares)	(273,000)
Outstanding at end of period (in shares)		8,425,000
Stock options vested and exercisable at end of period, number of shares (in shares)	2,765,000
Stock options vested and expected to vest at end of period, number of shares (in shares)	6,228,000
Weighted-average exercise price per share
Outstanding at beginning of period (in dollars per share)	$ 4.68
Granted (in dollars per share)	24.31
Exercised (in dollars per share)	3.65
Canceled (in dollars per share)	10.52
Outstanding at end of period (in dollars per share)	10.31	$ 4.68
Stock options vested and exercisable at end of period, weighted-average exercise price per share (in dollars per share)	3.54
Stock options vested and expected to vest at end of period, weighted-average exercise price per share (in dollars per share)	$ 10.31
Weighted-average remaining contractual term (In years)
Outstanding, weighted-average remaining contractual term	6 years 10 months 20 days	6 years 3 months 7 days
Stock options vested and exercisable, weighted-average remaining contractual term	4 years 10 months 17 days
Stock options vested and expected to vest, weighted-average remaining contractual term	6 years 10 months 20 days
Aggregate intrinsic value
Outstanding, aggregate intrinsic value	$ 198,434	$ 135,224
Stock options vested and exercisable, aggregate intrinsic value	106,787
Stock options vested and expected to vest, aggregate intrinsic value	$ 198,434

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Gross number of share options (or share units) granted during the period.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest exercisable or convertible options. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Number of fully vested and expected to vest exercisable options that may be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest exercisable or convertible options. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for fully vested and expected to vest exercisable or convertible options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Number of share options (or share units) exercised during the current period.

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