Prepaid Expenses and Other Current Assets (Tables)
12 Months Ended
Dec. 31, 2017
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]  
Schedule of Prepaid Expenses and Other Current Assets

Prepaid expenses and other current assets consist of the following:

 

     December 31,  
     2016      2017  
     RMB      RMB      US$  

Prepayments

     317,262        125,317        19,262  

Rental deposits

     1,494        11,918        1,832  

Interest receivable

     11,690        3,462        532  

Staff advances

     7,712        7,496        1,152  

Receivables from third-party payment platform

     12,327        14,757        2,268  

Other receivables

     26,734        23,173        3,562  
  

 

 

    

 

 

    

 

 

 
     377,219        186,123        28,608