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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Amount of gain (loss) on sale or disposal of an equity method investment.

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Long-term investments - Additional Information (Details) $ / shares in Units, ¥ in Thousands, $ in Thousands		3 Months Ended		9 Months Ended
	Jul. 31, 2021 USD ($) $ / shares shares	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Dec. 31, 2020	Jun. 30, 2017 CNY (¥) item
Equity And Cost Method Investments
Share of gain (loss) from equity method investment		$ (340)	$ (265)	$ (548)	$ (671)
JING
Equity And Cost Method Investments
Share of gain (loss) from equity method investment		340	$ 265	1,011	$ 671
Equity method investment, gain on disposal		$ 0		$ 463
Number of third-parties \| item							3
Capital contribution commitment \| ¥							¥ 26,250
Percentage of equity interest		18.00%		18.00%		20.00%
MacroGenics
Equity And Cost Method Investments
Share of gain (loss) from equity method investment		$ 9,930		$ 9,930
Capital contribution commitment	$ 30,000
Stock Issued During Period, Shares, Acquisitions \| shares	958,467
Issue price per share \| $ / shares	$ 31.30