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Significant Accounting Policies - Additional Information (Detail) $ in Thousands	6 Months Ended
	Jun. 30, 2025 USD ($) Segment shares	Jun. 16, 2025 shares	Feb. 20, 2025 USD ($)	Dec. 31, 2024 shares
Accounting Policy [Line Items]
Common Stock, Shares, Outstanding | shares	4,044,000			4,037,000
Common stock, shares authorized | shares	225,000,000	4,000,000		225,000,000
Number of reportable segment | Segment	1
Reverse Stock Split [Member]
Accounting Policy [Line Items]
Reverse stock split	1-for-25
Common Stock, Shares, Outstanding | shares		101,100,000
FibroGen International [Member]
Accounting Policy [Line Items]
Purchase price in cash | $			$ 85,000
Discontinued operations name	FibroGen International
Beijing Falikang Pharmaceutical Co Ltd | Beijing Kangda Yongfu Pharmaceutical Co., LTD [Member] | AstraZenecaAB [Member]
Accounting Policy [Line Items]
Percentage of outstanding shares acquired	51.10%		51.10%
Minimum [Member]
Accounting Policy [Line Items]
Unrestricted cash and cash equivalent balance required to maintain in accounts | $	$ 18,750
Debt Financing Agreement [Member] | Minimum [Member]
Accounting Policy [Line Items]
Unrestricted cash and cash equivalent balance required to maintain in accounts | $	$ 22,500

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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