Stock-based Compensation Plans - Schedule of the Company's Stock Option And RSU Activity (Detail) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
Nov. 12, 2020	Dec. 31, 2021	Dec. 31, 2020
Weighted Average Remaining Term (in Years), Outstanding as of December 31, 2021	15 years
Employee Stock Option [Member]
Number of Options, Outstanding at December 31, 2020		19,826,031
Number of Options, Granted		281,748
Number of Options, Exercised or released		(436,037)
Number of Options, Forfeited/Cancelled		(360,602)
Number of Options, Outstanding as of December 31, 2021		19,311,140
Number of Options, Vested and expected to vest, December 31, 2021		13,773,623
Number of Options, Exercisable and vested at December 31, 2021		12,126,266
Weighted average exercise price, Outstanding as of December 31, 2020		$ 1.29	$ 1.13
Weighted average exercise price, Granted	$ 1.13	1.13
Weighted Average Exercise Price, Exercised or released		(1.22)
Weighted Average Exercise Price, Forfeited/Cancelled		(1.13)
Weighted Average Exercise Price, Vested and expected to vest, December 31, 2021		1.13
Weighted Average Exercise Price, Exercisable and vested at December 31, 2021		$ 1.13
Weighted Average Remaining Term (in Years), Outstanding as of December 31, 2021		13 years 25 days
Weighted Average Remaining Contractual (Years), Vested and expected to vest, December 31, 2021		12 years 8 months 8 days
Weighted Average Remaining Contractual (Years), Exercisable and vested at December 31, 2021		13 years 4 months 20 days
Aggregate Intrinsic Value, Outstanding at December 31, 2021		$ 100,885
Aggregate Intrinsic Value,Vested and expected to vest, December 31, 2021		74,322
Aggregate Intrinsic Value, Exercisable and vested at December 31, 2021		$ 65,013
Restricted Stock Units (RSUs) [Member]
Number of RSUs, Granted		2,799,657
Number of RSUs, Exercised or released		(428,107)
Number of RSUs, Forfeited/Cancelled		(518,865)
Number of RSUs, Outstanding at December 31, 2021		1,852,685
Number of RSUs, Vested and expected to vest, December 31, 2021		1,852,685
Weighted Average Grant Date Fair Value, Granted		$ 6.03
Weighted Average Grant Date Fair Value, Exercised or released		6.28
Weighted Average Grant Date Fair Value, Forfeited/Cancelled		5.39
Weighted Average Grant Date Fair Value, Vested and expected to vest, December 31, 2021		6.14
Weighted Average Grant Date Fair Value, Exercisable and vested at December 31, 2021		$ 6.14

Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Exercised.

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Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Exercised In Period Weighted Average Grant Date Fair Value.

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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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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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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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Gross number of share options (or share units) granted during the period.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest exercisable or convertible options. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Number of fully vested and expected to vest exercisable options that may be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest exercisable or convertible options. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for fully vested and expected to vest exercisable or convertible options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted average remaining contractual term for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Number of share options (or share units) exercised during the current period.

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