Description of employee stock purchase plan offering period.

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Description of employee stock purchase plan offering period resets.

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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- Definition

Aggregate number of common shares reserved for future issuance.

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-Publisher FASB
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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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Amount of cost to be recognized for option under share-based payment arrangement.

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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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.

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No definition available.

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- Definition

The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

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- Definition

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

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Percentage of vesting of award under share-based payment arrangement.

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- Definition

Purchase price of common stock expressed as a percentage of its fair value.

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No definition available.

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Stock-Based Compensation - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Apr. 30, 2022	Apr. 30, 2021	Jan. 31, 2022
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized stock-based compensation expense related to stock option	$ 200
Stock options outstanding	3,020,268		5,726,893
Share-based compensation expense	$ 47,110	$ 41,790
Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Remaining weighted-average period	1 year
Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Remaining weighted-average period	3 years 21 days
Unrecognized stock-based compensation expense	$ 412,400
2015 Equity Incentive Plan \| Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period	4 years
2015 Equity Incentive Plan \| Class A Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares common stock reserved for issuance	23,256,575
2015 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of eligible compensation allowed to employees to purchase shares at a discount	15.00%
Description of offering period excluding initial offering period	The 2015 ESPP provides for 24-month offering periods beginning March 16 and September 16 of each year, and each offering period consists of four six-month purchase periods.
Purchase price of common stock, percentage	85.00%
Description of offering period resets	the offering period resets and the new lower price becomes the new offering price for a new 24 month offering period.
Unrecognized stock-based compensation expense	$ 16,600
2015 Employee Stock Purchase Plan \| Class A Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares common stock reserved for issuance	5,795,134
Fiscal 2022 Executive Bonus Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation expense	$ 4,500
Fiscal 2023 Executive Bonus Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized stock-based compensation expense	10,900
Share-based compensation expense	$ 2,400
Per Month after One Year of Vesting Commencement Date \| 2015 Equity Incentive Plan \| Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting percentage	6.25%
Per Quarter after One Year Of Vesting Commencement Date \| 2015 Equity Incentive Plan \| Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting percentage	6.25%
One Year from Vesting Commencement Date \| 2015 Equity Incentive Plan \| Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting percentage	25.00%