Amount, after adjustment, of cost-method investment. Adjustments include, but are not limited to, dividends received in excess of earnings after date of investment that are considered a return of investment and other than temporary impairments.

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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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Equity and cost method investments.

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Investment in Equity Investees - Additional Information (Details) ¥ in Millions	1 Months Ended	12 Months Ended
	Apr. 30, 2017 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2017 CNY (¥)	Jul. 05, 2017 USD ($)	Jul. 05, 2017 CNY (¥)	Jun. 30, 2017 USD ($) Investor	Jun. 30, 2017 CNY (¥) Investor	Oct. 31, 2016 USD ($)
Equity And Cost Method Investments [Line Items]
Cost method investments								$ 500,000
Quan Venture Fund I, L.P.
Equity And Cost Method Investments [Line Items]
Cash consideration for investment disposed	$ 500,000
Gain/loss recognized upon disposal	$ 0
JING
Equity And Cost Method Investments [Line Items]
Number of third-parties \| Investor						3	3
Capital contribution in cash				$ 1,900,000	¥ 13.1
Capital contribution commitment		$ 3,900,000	¥ 26.3			$ 3,900,000	¥ 26.3
Percentage of equity interest						20.00%	20.00%
Share of loss of investee		$ 249,652