Stock-Based Compensation - Schedule of Unvested Profits Interest Unit Activity (Detail) - Profit Interest Units - $ / shares	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Shares
Nonvested at the beginning	19,932,277	9,765,439
Nonvested, Granted	19,643,100	16,143,382
Nonvested, Vested	(7,044,620)	(4,790,327)
Nonvested, Forfeited	(10,588,658)	(1,186,217)
Nonvested at the ending	21,942,099	19,932,277
Expected to vest	21,942,099	19,932,277
Weighted average grant date fair value
Nonvested at the beginning	$ 0.19	$ 0.08
Nonvested, Granted	0.16	0.22
Nonvested, Vested	0.14	0.07
Nonvested, Forfeited	0.21	0.12
Nonvested at the ending	$ 0.18	$ 0.19

No definition available.

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- Definition

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

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- Definition

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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- Definition

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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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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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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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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