PROPERTY AND EQUIPMENT, NET (Schedule of Property and Equipment) (Details) - CNY (¥) ¥ in Thousands |
Dec. 31, 2017 |
Dec. 31, 2016 |
|---|---|---|
| Property, Plant and Equipment [Line Items] | ||
| Property and equipment | ¥ 780,282 | ¥ 635,864 |
| Less: accumulated depreciation | (260,591) | (198,527) |
| Property and equipment, net | 519,691 | 437,337 |
| Office buildings [Member] | ||
| Property, Plant and Equipment [Line Items] | ||
| Property and equipment | 288,046 | 281,541 |
| Furniture [Member] | ||
| Property, Plant and Equipment [Line Items] | ||
| Property and equipment | 29,405 | 18,078 |
| Office equipment [Member] | ||
| Property, Plant and Equipment [Line Items] | ||
| Property and equipment | 362,254 | 271,862 |
| Leasehold improvements [Member] | ||
| Property, Plant and Equipment [Line Items] | ||
| Property and equipment | ¥ 100,577 | ¥ 64,383 |