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Discontinued Operations and Divestiture - Schedule of Carrying Value of Assets and Liabilities of Discontinued Operations (Detail) - USD ($) $ in Thousands | Sep. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Assets |  |
Total current assets held for sale | $ 0 | $ 110,849
Total long-term assets held for sale | 0 | 16,611
Liabilities |  |
Total current liabilities held for sale | 0 | 38,917
Total long-term liabilities held for sale | $ 0 | 356
FibroGen International [Member] |  |
Assets |  |
Cash and cash equivalents |  | 51,696
Accounts receivable, net |  | 18,443
Inventories |  | 15,547
Prepaid expenses and other current assets |  | 25,163
Total current assets held for sale |  | 110,849
Property and equipment, net |  | 7,041
Equity method investment in unconsolidated variable interest entity |  | 6,864
Operating lease right-of-use assets |  | 1,716
Other assets |  | 990
Total long-term assets held for sale |  | 16,611
Liabilities |  |
Accounts payable |  | 26,974
Accrued and other current liabilities |  | 10,679
Operating lease liabilities, current |  | 1,264
Total current liabilities held for sale |  | 38,917
Operating lease liabilities, non-current |  | 356
Total long-term liabilities held for sale |  | $ 356

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