Income Taxes - Components of Deferred Tax Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Deferred tax assets
NOL carryforwards	$ 229,476	$ 218,905
R&D credit carryforwards	74,702	63,886
Stock-based compensation	51,170	47,547
Charitable contributions	41,355	28,470
Lease liabilities	15,550	11,675
Intangibles	6,741	7,109
Capitalized R&D		6,073
Other	11,700	9,390
Total deferred tax assets	430,694	393,055
Valuation allowance	(416,630)	(380,533)
Deferred tax liabilities
Right-of-use assets	(14,063)	(11,142)
Propery and equipment	(1)	(1,380)
Total deferred tax liabilities	(14,064)	(12,522)
Total net deferred tax assets	$ 0	$ 0

Deferred tax assets lease obligations.

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Deferred tax liabilities right of use assets.

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Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences with jurisdictional netting.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible charitable contribution carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from intangible assets including goodwill.

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

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from in-process research and development costs expensed in connection with a business combination.

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Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting.

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

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from share-based compensation.

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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 property, plant, and equipment.

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