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Commitments and Contingencies - Additional Information (Detail) $ in Millions | 2 Months Ended | 6 Months Ended
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May 31, 2021 PutativeClassAction | Jun. 30, 2023 USD ($)
Commitments And Contingencies [Line Items] |  |
Operating lease liability |  | $ 84.8
Outstanding non-cancelable purchase obligations |  | 40.8
Putative securities class action complaints filed | PutativeClassAction | 5 |
Manufacture and Supply of Roxadustat [Member] |  |
Commitments And Contingencies [Line Items] |  |
Outstanding non-cancelable purchase obligations |  | 2.5
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 |  | 15.9
Research and Preclinical Stage Development Programs [Member] |  |
Commitments And Contingencies [Line Items] |  |
Maximum future milestone payments |  | $ 697.9

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