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Commitments and Contingencies - Additional Information (Detail) $ in Millions	2 Months Ended	9 Months Ended	32 Months Ended
	May 31, 2021 PutativeClassAction	Sep. 30, 2024 USD ($)	Apr. 03, 2024 ShareholderDerivative	Dec. 31, 2023 USD ($)	Oct. 17, 2023 USD ($)
Commitments And Contingencies [Line Items]
Operating lease liability		$ 2.0
Number of complaints filed	5		7
Litigation settlement amount				$ 28.5	$ 28.5
Manufacture and Supply of Roxadustat [Member]
Commitments And Contingencies [Line Items]
Outstanding non-cancelable purchase obligations		1.0
Other Purchases [Member]
Commitments And Contingencies [Line Items]
Outstanding non-cancelable purchase obligations		6.0
Research and Preclinical Stage Development Programs [Member]
Commitments And Contingencies [Line Items]
Maximum future milestone payments		$ 697.9

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Commitments and contingencies.

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Amount of contractual obligation, including, but not limited to, long-term debt, lease obligation, purchase obligation, and other commitments.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
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Amount of loss contingency liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 450
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-Section 50
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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 450
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Present value of lessee's discounted obligation for lease payments from operating lease.

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