Commitments and Contingencies - Summary of Future Minimum Lease Payments under Non-Cancellable Operating Leases (Detail) In Thousands, unless otherwise specified	Sep. 30, 2014 USD ($)	Sep. 30, 2014 CNY	Dec. 31, 2013 USD ($)	Dec. 31, 2013 CNY
Commitments and Contingencies Disclosure [Abstract]
2014			$ 4,453	26,958
Three months ending December 31, 2014	1,562	9,586
2015	6,028	37,000	4,246	25,707
2016	4,956	30,421	3,634	22,001
2017 and thereafter
Total future minimum lease payments under non-cancellable leases	$ 12,546	77,007	$ 12,333	74,666

Operating Leases Future Minimum Payments Due In Year Four And Thereafter

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Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 10

-Section 55

-Paragraph 40

-Subparagraph (Note 3)

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-Publisher FASB

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Amount of required minimum rental payments maturing in the next fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

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Amount of required minimum rental payments maturing in the third fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

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Amount of required minimum rental payments maturing in the second fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Amount of required minimum rental payments maturing in the remainder of the fiscal year following the latest fiscal year ended for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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