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Commitments and Contingencies - Additional Information (Detail) $ in Millions | 1 Months Ended | 9 Months Ended
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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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