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Equity method investment - Variable Interest Entity - Summary of Equity Method Investment (Detail) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Acquisition And Variable Interest Entity [Line Items] |  |  |
Beginning balance | $ 5,061 |  |
Share of Net Income | 2,638 | $ 1,573 | $ 1,007
Ending balance | $ 5,290 | 5,061 |
Beijing Falikang Pharmaceutical Co. Ltd [Member] |  |  |
Acquisition And Variable Interest Entity [Line Items] |  |  |
Ownership Percentage | 51.10% |  |
Beginning balance | $ 5,061 |  |
Share of Net Income | 2,638 |  |
Dividend Received | (2,255) |  |
Currency Translation | (154) |  |
Ending balance | $ 5,290 | $ 5,061 |

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