Property and Equipment, Net - Summary of Property and Equipment (Detail) ¥ in Thousands, $ in Thousands |
Dec. 31, 2017
CNY (¥)
|
Dec. 31, 2017
USD ($)
|
Dec. 31, 2016
CNY (¥)
|
|---|---|---|---|
| At cost: | |||
| Property and equipment, gross | ¥ 380,717 | $ 58,515 | ¥ 307,646 |
| Less: Accumulated depreciation | (250,395) | (38,485) | (173,072) |
| Property and equipment, net | 130,322 | 20,030 | 134,574 |
| Electronic Equipment [Member] | |||
| At cost: | |||
| Property and equipment, gross | 301,783 | 46,383 | 234,360 |
| Office Equipment [Member] | |||
| At cost: | |||
| Property and equipment, gross | 1,361 | 209 | 1,024 |
| Motor Vehicles [Member] | |||
| At cost: | |||
| Property and equipment, gross | 2,855 | 439 | 3,418 |
| Software [Member] | |||
| At cost: | |||
| Property and equipment, gross | 34,310 | 5,273 | 26,480 |
| Leasehold Improvements [Member] | |||
| At cost: | |||
| Property and equipment, gross | ¥ 40,408 | $ 6,211 | ¥ 42,364 |