Income Taxes - Summary of Significant Components of Company's Net Deferred Tax Asset (Detail) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Income Tax Disclosure [Abstract]
Net operating losses	$ 490,891	$ 428,785
Tax credits	145,113	133,602
Capitalized research and development expenses	128,001	110,690
Stock-based compensation	23,967	53,860
Accrued expenses	5,491	7,018
Depreciation and amortization	1,914	1,456
Lease liability	2,748	1,207
Right of use asset	(2,497)	(1,042)
Other	1,090	(382)
Total net deferred tax asset before valuation allowance	796,718	735,194
Valuation allowance	$ (796,718)	$ (735,194)

Deferred tax assets right of use asset.

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- Definition

Deferred tax assets stock based compensation.

+ References

No definition available.

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- Definition

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
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-2

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- Definition

Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary difference from in-process research and development cost acquired in business combination or from joint venture formation or both.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-6

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- Definition

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

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- Definition

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 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.

+ References

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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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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-2

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

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- References

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