Fair value of restricted stock units vested total.

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Share-based Compensation Arrangement by Share-based Payment Award, Stock Incentive Plans

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Number of shares of equity interests issued or issuable to acquire entity.

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

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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 expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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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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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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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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Number of additional shares authorized for issuance under share-based payment arrangement.

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Number of shares authorized for issuance under share-based payment arrangement.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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Stock Plans - Additional Information (Detail) $ / shares in Units, shares in Thousands, $ in Thousands			3 Months Ended	12 Months Ended
	Oct. 22, 2020 shares	Oct. 01, 2019	Dec. 31, 2020 $ / shares shares	Mar. 31, 2021 USD ($) stock_plan $ / shares shares	Mar. 31, 2020 USD ($)	Mar. 31, 2019 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted, vesting period				3 years
Unrecognized stock-based compensation expense \| $				$ 120,658
Awards expected to be recognized over a weighted average period (in years)				1 year 10 months 17 days
Total intrinsic value of options exercised \| $				$ 4,306	$ 13,428	$ 39,502
Total fair value of restricted stock units - vested \| $				72,544	48,221	82,957
Restructuring \| $				$ 23,471	$ 21,348	$ 14,765
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value, granted (in dollars per share) \| $ / shares				$ 42.04
2016 Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares of common stock that may be delivered under plan (in shares) \| shares	8,050
Addition shares authorized (in shares) \| shares	1,000
Options available for future grant (in shares) \| shares				2,110
2006 Long-Term Stock Inventive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock incentive plans \| stock_plan				1
Hedvig, Inc. \| Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares Issued in acquisition \| shares			1,018
Weighted average grant date fair value, granted (in dollars per share) \| $ / shares			$ 44.49
Stock options granted, vesting period		3 years