Number of investments.

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Amount of contractual obligation, including but not limited to, long-term debt, capital lease obligations, operating lease obligations, purchase obligations, and other commitments.

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Amount of income (loss) for proportionate share of equity method investee's income (loss).

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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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Long-Term Investments - Additional Information (Details) ¥ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021 CNY (¥) Investment	Dec. 31, 2021 USD ($)	Dec. 31, 2020 CNY (¥)	Dec. 31, 2019 CNY (¥)
Schedule Of Equity Method Investments [Line Items]
(Loss) gain from equity method investments	¥ (4,886)	$ (767)	¥ 1,349	¥ (136)
Impairment loss on long-term investments	5,000	$ 785	¥ 882
Long-term Investments
Schedule Of Equity Method Investments [Line Items]
Investment committed amount but not yet paid \| ¥	¥ 9,840
Limited Partnerships
Schedule Of Equity Method Investments [Line Items]
Number of investments	3
Private Company
Schedule Of Equity Method Investments [Line Items]
Number of investments	2