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Long-Term Investments - Additional Information (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019 CNY (¥) Investment	Dec. 31, 2019 USD ($) Investment	Dec. 31, 2018 CNY (¥)	Dec. 31, 2017 CNY (¥)
Schedule Of Equity Method Investments [Line Items]
(Loss) gain from equity method investments	¥ (136,000)	$ (20)	¥ 1,710,000	¥ (4,890,000)
Impairment loss | ¥	¥ 0		¥ 0
Limited Partnerships
Schedule Of Equity Method Investments [Line Items]
Number of investments | Investment	3	3

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Number of investments.

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Amount of other-than-temporary impairment (OTTI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), recognized in earnings and other comprehensive loss (OCI).

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