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Equity method investment - Variable Interest Entity - Summary of Equity Method Investment (Detail) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Acquisition And Variable Interest Entity [Line Items] |  |  |
Beginning balance | $ 3,825 |  |
Investment income (loss) in unconsolidated variable interest entity | 1,573 | $ 1,007 | $ (202)
Ending balance | $ 5,061 | 3,825 |
Beijing Falikang Pharmaceutical Co. Ltd [Member] |  |  |
Acquisition And Variable Interest Entity [Line Items] |  |  |
Ownership Percentage | 51.10% |  |
Beginning balance | $ 3,825 |  |
Investment income (loss) in unconsolidated variable interest entity | 1,573 |  |
Currency Translation | (337) |  |
Ending balance | $ 5,061 | $ 3,825 |

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