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Commitments and Contingencies - Additional Information (Detail) $ in Millions | 2 Months Ended | 3 Months Ended
--- | --- | ---
May 31, 2021 PutativeClassAction | Mar. 31, 2023 USD ($)
Commitments And Contingencies [Line Items] |  |
Operating lease liability |  | $ 86.8
Outstanding non-cancelable purchase obligations |  | 51.9
Putative securities class action complaints filed | PutativeClassAction | 5 |
Manufacture and Supply of Roxadustat [Member] |  |
Commitments And Contingencies [Line Items] |  |
Outstanding non-cancelable purchase obligations |  | 4.1
Manufacture and Supply of Pamrevlumab [Member] |  |
Commitments And Contingencies [Line Items] |  |
Outstanding non-cancelable purchase obligations |  | 22.4
Other Purchases [Member] |  |
Commitments And Contingencies [Line Items] |  |
Outstanding non-cancelable purchase obligations |  | 25.4
Research and Preclinical Stage Development Programs [Member] |  |
Commitments And Contingencies [Line Items] |  |
Maximum future milestone payments |  | $ 697.9

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