Summary of Significant Accounting Policies - Additional Information (Detail) |
12 Months Ended |
|---|---|
|
Dec. 31, 2016
USD ($)
| |
| Accounting Policies [Abstract] | |
| Estimated useful life | 5 years |
| Impairment losses on long-lived assets | $ 0 |
| Percentage of likelihood to be realized upon ultimate settlement, description | 50.00% |