Number of employee equity plans.

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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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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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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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Stock-Based Compensation - Additional Information (Details) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 31, 2025 USD ($) Plan shares	Jul. 31, 2024 USD ($)	Jul. 31, 2025 USD ($) Plan $ / shares shares	Jul. 31, 2024 USD ($)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of employee equity plans \| Plan	2		2
Share-based compensation expense	$ 60,758	$ 55,111	$ 115,652	$ 106,273
Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Remaining weighted-average period			2 years 9 months
Unrecognized stock-based compensation expense	$ 447,900		$ 447,900
Number of market based restricted stock units granted \| shares			7,256,188
Share based compensation, average grant date fair value \| $ / shares			$ 30.74
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	3,692,406		3,692,406
2015 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Remaining weighted-average period			1 year 1 month 9 days
Unrecognized stock-based compensation expense	$ 3,800		$ 3,800
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	2,059,623		2,059,623
Executive Bonus Plans \| Performance-Based Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation expense			$ 7,900
Fiscal 2026 Executive Bonus Plan \| Performance-Based Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized stock-based compensation expense	$ 10,400		$ 10,400