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v3.25.2

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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