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Commitments and Contingencies - Additional Information (Detail) $ in Millions | 2 Months Ended | 9 Months Ended |
--- | --- | --- | ---
May 31, 2021 PutativeClassAction | Sep. 30, 2023 USD ($) | Oct. 17, 2023 USD ($)
Commitments And Contingencies [Line Items] |  |  |
Operating lease liability |  | $ 81.9 |
Outstanding non-cancelable purchase obligations |  | 37.8 |
Putative securities class action complaints filed | PutativeClassAction | 5 |  |
Litigation settlement amount |  | 28.5 | $ 28.5
Manufacture and Supply of Roxadustat [Member] |  |  |
Commitments And Contingencies [Line Items] |  |  |
Outstanding non-cancelable purchase obligations |  | 2.2 |
Manufacture and Supply of Pamrevlumab [Member] |  |  |
Commitments And Contingencies [Line Items] |  |  |
Outstanding non-cancelable purchase obligations |  | 22.8 |
Other Purchases [Member] |  |  |
Commitments And Contingencies [Line Items] |  |  |
Outstanding non-cancelable purchase obligations |  | 12.8 |
Research and Preclinical Stage Development Programs [Member] |  |  |
Commitments And Contingencies [Line Items] |  |  |
Maximum future milestone payments |  | $ 697.9 |

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