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Income Taxes - Schedule of Significant Components of Deferred Tax Assets (Detail) - USD ($) $ in Thousands | Dec. 31, 2024 | Dec. 31, 2023
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Components of Deferred Tax Assets and Liabilities [Abstract] |  |
Federal and state net operating loss carryforwards | $ 206,365 | $ 175,258
Tax credit carryforwards | 129,320 | 123,156
Foreign net operating loss carryforwards | 120 | 157
Capitalized research and development expenses | 83,329 | 81,697
Stock-based compensation | 6,365 | 7,269
Lease obligations | 22 | 16,508
Reserves and accruals | 4,418 | 5,475
Deferred revenue | 7,785 | 10,038
Intangible assets | 15,036 | 16,517
Other | 0 | 5
Subtotal | 452,760 | 436,080
Less: Valuation allowance | (452,740) | (426,355)
Net deferred tax assets | 20 | 9,725
Fixed assets | (20) | (9,725)
Non-deductible accrued expenses | 0 | 0
Net deferred tax liabilities | (20) | (9,725)
Total net deferred tax assets | $ 0 | $ 0

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