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Commitments and Contingencies - Additional Information (Detail) $ in Thousands | 1 Months Ended | 2 Months Ended | 32 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | ---
May 31, 2025 USD ($) | May 31, 2021 PutativeClassAction | Apr. 03, 2024 ShareholderDerivative | Jun. 30, 2025 USD ($) | Dec. 31, 2024 USD ($) | Oct. 17, 2023 USD ($)
Commitments And Contingencies [Line Items] |  |  |  |  |  |
Number of complaints filed |  | 5 | 7 |  |  |
Litigation settlement amount |  |  |  |  | $ 28,500 | $ 28,500
Civil penalty payment | $ 1,250 |  |  |  |  |
General Purchases And Other Programs [Member] |  |  |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |  |  |
Recorded unconditional purchase obligation |  |  |  | $ 3,100 |  |
Manufacture and Supply of Roxadustat [Member] |  |  |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |  |  |
Recorded unconditional purchase obligation |  |  |  | $ 500 |  |

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