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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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Amount of receivable related to a loss contingency accrual that is expected to be collected within one year or the normal operating cycle, if longer. For example, an insurance recovery receivable.

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Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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