Stock-Based Compensation - Summary of The Activity of Restricted Stock And Restricted Stock Units Granted By The Company (Parenthetical) (Detail) - shares		9 Months Ended
Mar. 12, 2021	Sep. 30, 2021
Share-based compensation arrangement by share-based payment award, award vesting period	4 years
IPO [Member]
Share-based compensation arrangement by share-based payment award, award vesting period	1 year
Percentage of vesting of restricted stock and restricted stock units	25.00%
Restricted Stock [Member]
Number of shares available for grant	1,660,677	8,824,045
Number of shares forfeited during period		4,682,178
Restricted Stock Units (RSUs) [Member]
Number of shares available for grant	98,993	288,724
Stock issued during period, shares, conversion of units		1,198,219
Number of shares forfeited during period		17,924
Series A Redeemable Convertible Preferred Shares [Member] \| Restricted Stock [Member]
Number of shares cancelled during period		16,655,197

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 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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Percentage of vesting of award under share-based payment arrangement.

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The number of shares issued during the period upon the conversion of units. An example of a convertible unit is an umbrella partnership real estate investment trust unit (UPREIT unit).

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