Stock-Based Compensation - RSUs and Payroll Reduction Program (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	12 Months Ended
Dec. 31, 2020	Dec. 31, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for issuance	11,137,824	11,137,824
Stock based compensation expense		$ 11,409	$ 35,972
Cost not recognized	$ 5,245	$ 5,245
Restricted stock units
Number of Restricted Stock Awards
Shares granted		2,450,718
Canceled		(35,578)
Ending Balance	2,415,140	2,415,140
Weighted Average Fair Value
Granted		$ 3.69
Canceled		3.44
Ending balance	$ 3.64	$ 3.64
Employee awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for issuance	6,414,611	6,414,611
Stock based compensation expense		$ 9,793	$ 2,740
Employee awards \| Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reduced cash payroll costs		$ 3,979
Shares reserved for issuance	2,356,045	2,356,045
Shares issued		2,356,045
Stock based compensation expense	$ 6,506
Cost not recognized	$ 1,605	$ 1,605

Amount of cash payroll cost reduced in exchange for a commitment by the Company to provide RSUs.

No definition available.

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

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

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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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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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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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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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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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Number of shares issued during the period related to Restricted Stock Awards, net of any shares forfeited.

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