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Variable Interest Entity - Additional Information (Detail)	Mar. 31, 2021
Beijing Kangda Yongfu Pharmaceutical Co., LTD [Member] | Beijing Falikang Pharmaceutical Co Ltd | FibroGen Beijing [Member] | AstraZenecaAB [Member]
Acquisition And Variable Interest Entity [Line Items]
Percentage of outstanding shares acquired	51.10%

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- Definition

Acquisition and variable interest entity line items.

+ 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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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- Details

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- Details

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- Details

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