Accrued Expenses - Schedule of Accrued Expenses (Detail) - USD ($) $ in Thousands |
Dec. 31, 2015 |
Dec. 31, 2014 |
|---|---|---|
| Payables and Accruals [Abstract] | ||
| Accrued payroll and related expenses | $ 1,582 | $ 1,495 |
| Accrued professional fees | 471 | 338 |
| Accrued research and development expenses | 430 | 540 |
| Accrued insurance | 389 | 389 |
| Accrued other | 507 | 254 |
| Total | $ 3,379 | $ 3,016 |