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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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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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