Income Taxes - Summary of Significant Components of Company's Net Deferred Tax Asset (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Net operating losses	$ 305,824	$ 222,607
Capitalized start-up costs	735	873
Tax credit carryforwards	106,176	90,460
Accrued expenses	6,684	3,157
Depreciation and amortization	1,401	1,614
Stock-based compensation	49,281	56,520
Right of use asset	(3,702)	(5,981)
Lease liability	4,236	6,705
Other	(31)	148
Total net deferred tax asset before valuation allowance	470,604	376,103
Valuation allowance	$ (470,604)	$ (376,103)

Deferred tax assets capitalized start-up costs.

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Deferred tax assets right of use asset.

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Deferred tax assets stock based compensation.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards.

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Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences, classified as other.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from property, plant, and equipment.

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Amount, before allocation of a valuation allowances, of deferred tax assets attributable to deductible tax credit carryforwards including, but not limited to, research, foreign, general business, alternative minimum tax, and other deductible tax credit carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from accrued liabilities.

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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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Amount of deferred tax liability attributable to taxable temporary differences from leasing arrangements.

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