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Balance Sheet Components - Additional Information (Detail) - USD ($) $ in Thousands | 1 Months Ended | 3 Months Ended | 9 Months Ended |
--- | --- | --- | --- | ---
Jul. 31, 2024 | Sep. 30, 2025 | Sep. 30, 2025 | Dec. 31, 2024
Schedule of Available-for-sale Securities [Line Items] |  |  |  |
API and bulk drug product price true-up |  | $ 12,398 | $ 12,398 | $ 13,071
Accrued litigation settlement |  |  |  | 28,500
Litigation settlement receivable |  | 0 | 0 | $ 28,500
Restructuring plan, expected reduction to workforce, percentage | 75.00% |  |  |
Cash payments for restructuring |  | 900 | 3,200 |
Accrued restructuring charges |  | 800 | $ 800 |
Available for sale investments contractual maturities |  |  | 2 years |
Closing of Divestiture of FibroGen International [Member] |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |
Litigation settlement receivable |  | $ 10,000 | $ 10,000 |

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