Summary of Significant Accounting Policies - Schedule of Balances of Registered Capital, Additional Paid-in-Capital and Statutory Reserves (Detail) - USD ($) $ in Thousands |
Dec. 31, 2015 |
Dec. 31, 2014 |
|---|---|---|
| Accounting Policies and General Information [Line Items] | ||
| Additional paid-in capital | $ 458,270 | $ 446,202 |
| Statutory reserves | 5,132 | 5,132 |
| China [Member] | ||
| Accounting Policies and General Information [Line Items] | ||
| Registered capital | 112,435 | 54,467 |
| Additional paid-in capital | 161 | 161 |
| Statutory reserves | 5,132 | 5,132 |
| Total | $ 117,728 | $ 59,760 |