Stock-based Compensation - Summary of Company's Restricted Stock Units And Unregistered Restricted Stock Awards Activity (Parenthetical) (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation by share based payment arrangement unrecognized compensation equity instruments other than options period for recognition	3 years 3 months 18 days
Allocated share based compensation	$ 50,744	$ 42,257
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation by share based payment arrangement unrecognized compensation equity instruments other than options	$ 494,200
Share based compensation by share based payment arrangement unrecognized compensation equity instruments other than options period for recognition	3 years 8 months 12 days
Allocated share based compensation	$ 21,300
Restricted Stock Units (RSUs) [Member] \| Granted After Direct Listing [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation by share based payment arrangement vesting period	4 years
Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation by share based payment arrangement unrecognized compensation equity instruments other than options	$ 8,200
Share based compensation by share based payment arrangement unrecognized compensation equity instruments other than options period for recognition	2 years 8 months 12 days

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

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-Name Accounting Standards Codification
-Topic 718
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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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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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