Income Tax - Schedule of Reconciliations of PRC Statutory Income Tax Rate and Group's Effective Income Tax Rate (Details) - PRC |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
|
| Income Taxes [Line Items] | |||
| Statutory income tax rate | 25.00% | 25.00% | 25.00% |
| Share-based compensations | (3.27%) | (2.92%) | (3.68%) |
| Non-deductible expenses | (0.79%) | (1.59%) | (7.19%) |
| Effect of different tax rate of subsidiary operation in other jurisdictions | (3.06%) | (3.33%) | (7.15%) |
| Changes in valuation allowance | (17.88%) | (17.16%) | (6.98%) |