Stock Plans - Employee Stock Purchase Plan (Details) - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
Mar. 31, 2026	Mar. 31, 2025	Mar. 31, 2024
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	$ 123,425	$ 113,262	$ 94,551
Unrecognized stock-based compensation expense	$ 172,437
ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Purchase price as a percentage of fair market value	85.00%
Length of offering period (in months)	6 months
Maximum employee payroll percent deduction of salary	10.00%
Maximum amount of stock purchasable by employees within a calendar year	$ 25
Number of shares purchased by employees (in shares)	146	119	188
Proceeds received	$ 14,503	$ 11,922	$ 10,578
Compensation expense	5,523	$ 3,898	$ 3,146
Unrecognized stock-based compensation expense	$ 2,450

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

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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The cash inflow associated with the amount received from the stock plan during the period.

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

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

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Number of shares issued during the period as a result of an employee stock purchase plan.

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