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

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Aggregate number of common shares reserved for future issuance.

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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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- Definition

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

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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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Stock-Based Compensation - Additional Information (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 31, 2026 USD ($) Plan shares	Jul. 31, 2025 USD ($)	Jul. 31, 2026 USD ($) Plan shares	Jul. 31, 2025 USD ($)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of employee equity plans \| Plan	2		2
Share-based compensation expense	$ 61,363	$ 60,758	$ 117,676	$ 115,652
Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Remaining weighted-average period			2 years 8 months 1 day
Unrecognized stock-based compensation expense	$ 426,700		$ 426,700
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 \| shares	10,235,803		10,235,803
2015 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Remaining weighted-average period			1 year 4 months 6 days
Unrecognized stock-based compensation expense	$ 18,000		$ 18,000
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 \| shares	6,840,600		6,840,600
Executive Bonus Plans \| Performance-Based Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation expense	$ 4,200		$ 10,800
Fiscal 2027 Executive Bonus Plan \| Performance-Based Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized stock-based compensation expense	$ 11,700		$ 11,700