Significant Accounting Policies - Additional Information (Detail) $ in Millions	3 Months Ended
Mar. 31, 2025 USD ($) Segment	Feb. 20, 2025 USD ($)
Accounting Policy [Line Items]
Number of reportable segment \| Segment	1
FibroGen International [Member]
Accounting Policy [Line Items]
Purchase price in cash		$ 85
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	$ 27
Debt Financing Agreement [Member] \| Minimum [Member]
Accounting Policy [Line Items]
Unrestricted cash and cash equivalent balance required to maintain in accounts	$ 30

Accounting policy.

No definition available.

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- Definition

Disposal group, including discontinued operation, cash consideration.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Unrestricted cash and cash equivalent balance maintain in accounts.

+ References

No definition available.

+ Details

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479328/805-10-50-2

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- Definition

Name of component or group of components disposed of or classified as held-for-sale representing strategic shift that has or will have major effect on operation and financial result.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483499/205-20-50-1

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 47
-Subparagraph (a)
-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/exampleRef
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Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
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-Section 50
-Paragraph 18
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-18

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- Details

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- Details

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- Details

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