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Commitments and Contingencies - Additional Information (Detail) $ in Millions	1 Months Ended		9 Months Ended
	May 31, 2021 PutativeClassAction	Apr. 30, 2021 PutativeClassAction	Sep. 30, 2021 USD ($)
Commitments And Contingencies [Line Items]
Outstanding non-cancelable purchase obligations			$ 77.4
Putative securities class action complaints filed | PutativeClassAction	2	3
Manufacture and Supply of Roxadustat [Member]
Commitments And Contingencies [Line Items]
Outstanding non-cancelable purchase obligations			22.0
Manufacture and Supply of Pamrevlumab [Member]
Commitments And Contingencies [Line Items]
Outstanding non-cancelable purchase obligations			46.5
Other Purchases [Member]
Commitments And Contingencies [Line Items]
Outstanding non-cancelable purchase obligations			8.9
Research and Pre-Clinical Stage Development Programs [Member]
Commitments And Contingencies [Line Items]
Maximum future milestone payments			$ 359.1

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- Definition

Commitments and contingencies.

+ References

No definition available.

+ Details

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- Definition

Maximum future milestone payments.

+ References

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

The total number of new claims filed pertaining to a loss contingency during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14435-108349

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