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Commitments and Contingencies - Additional Information (Detail) $ in Millions	2 Months Ended	9 Months Ended
	May 31, 2021 PutativeClassAction	Sep. 30, 2022 USD ($)
Commitments And Contingencies [Line Items]
Operating lease liability		$ 92.6
Outstanding non-cancelable purchase obligations		51.2
Putative securities class action complaints filed | PutativeClassAction	5
Manufacture and Supply of Roxadustat [Member]
Commitments And Contingencies [Line Items]
Outstanding non-cancelable purchase obligations		7.8
Manufacture and Supply of Pamrevlumab [Member]
Commitments And Contingencies [Line Items]
Outstanding non-cancelable purchase obligations		21.0
Other Purchases [Member]
Commitments And Contingencies [Line Items]
Outstanding non-cancelable purchase obligations		22.3
Research and Pre-Clinical Stage Development Programs [Member]
Commitments And Contingencies [Line Items]
Maximum future milestone payments		$ 697.9

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- Definition

Commitments and contingencies.

+ References

No definition available.

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- Definition

Maximum future milestone payments.

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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.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=121557415&loc=d3e14435-108349

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=121557415&loc=d3e14557-108349

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=123391704&loc=SL77918627-209977

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