Prepaid Expenses and Other Current Assets - Schedule of Prepaid Expenses and Other Current Assets (Detail)
¥ in Thousands, $ in Thousands
Dec. 31, 2017
CNY (¥)
Dec. 31, 2017
USD ($)
Dec. 31, 2016
CNY (¥)
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]      
Prepayments ¥ 125,317 $ 19,262 ¥ 317,262
Rental deposits 11,918 1,832 1,494
Interest receivable 3,462 532 11,690
Staff advances 7,496 1,152 7,712
Receivables from third-party payment platform 14,757 2,268 12,327
Other receivables 23,173 3,562 26,734
Prepaid expenses and other current assets ¥ 186,123 $ 28,608 ¥ 377,219