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Equity method investment - Variable Interest Entity - Summary of Equity Method Investment (Detail) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022
Acquisition And Variable Interest Entity [Line Items] |  |  |  |
Beginning balance |  |  | $ 5,061 |
Share of Net Income | $ 677 | $ 407 | 2,023 | $ 1,293
Ending balance | $ 4,534 |  | $ 4,534 |
Beijing Falikang Pharmaceutical Co. Ltd [Member] |  |  |  |
Acquisition And Variable Interest Entity [Line Items] |  |  |  |
Ownership Percentage | 51.10% |  | 51.10% |
Beginning balance |  |  | $ 5,061 |
Share of Net Income |  |  | 2,023 |
Dividend Received |  |  | (2,255) |
Currency Translation |  |  | (295) |
Ending balance | $ 4,534 |  | $ 4,534 |

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