Income Taxes - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Income Taxes [Line Items]
Foreign	$ 4	$ 16
Valuation allowance	(242,590)	(192,513)
Increase in valuation allowance due to deferred tax assets	50,100	39,500
Federal net operating loss carryforwards	746,600
State net operating loss carryforwards	545,500
Foreign loss carryforwards	500
Research and development tax credits	27,341	25,424
Unrecognized tax benefits, if recognized, would affect the effective tax rate	0	$ 100
Federal loss carryforwards expire in the next five years	93,100
Federal
Income Taxes [Line Items]
Research and development tax credits	19,000
State
Income Taxes [Line Items]
Research and development tax credits	$ 10,600

Income Taxes [Line Items]

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Amount of current foreign income tax expense (benefit) pertaining to income (loss) from continuing operations.

+ References

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible domestic operating loss carryforwards. Excludes state and local operating loss carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible foreign operating loss carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible state and local operating loss carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards that are subject to expiration dates.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible research tax credit carryforwards.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset.

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