Cost of Revenues - Schedule of Cost of Revenues (Detail)
¥ in Thousands, $ in Thousands
12 Months Ended
Dec. 31, 2017
CNY (¥)
Dec. 31, 2017
USD ($)
Dec. 31, 2016
CNY (¥)
Dec. 31, 2015
CNY (¥)
Cost of Revenue [Abstract]        
Content-related costs ¥ 390,885 $ 60,078 ¥ 269,313 ¥ 184,635
Depreciation and amortization 41,579 6,391 42,570 43,160
Bandwidth and internet data center 89,889 13,816 51,766 38,893
VAT and surcharges 484,811 74,513 349,373 269,491
Cost of sales, including tax 351,521 54,028 1,680,143 132,942
Cost of revenues ¥ 1,358,685 $ 208,826 ¥ 2,393,165 ¥ 669,121