Commitments - Additional Information (Detail) - USD ($) $ in Thousands |
12 Months Ended | |||
|---|---|---|---|---|
Jul. 09, 2015 |
Dec. 31, 2015 |
Dec. 31, 2014 |
Dec. 31, 2013 |
|
| Operating Leased Assets [Line Items] | ||||
| Noncancelable operating lease expire date | Feb. 28, 2013 | |||
| Noncancelable operating leases renewal option period | 3 years | |||
| Deferred liability related to facility lease | $ 41 | |||
| Lease amendment, commencement Date | Jul. 11, 2014 | |||
| Lease termination date | Dec. 31, 2015 | |||
| Noncancelable operating lease rent expenses | $ 920 | $ 766 | $ 598 | |
| Office Laboratory and Vivarium Space Facility Lease [Member] | ||||
| Operating Leased Assets [Line Items] | ||||
| Noncancelable operating lease expire date | Feb. 28, 2021 | |||
| Noncancelable operating leases renewal option period | 3 years | |||
| Extended Lease | ||||
| Operating Leased Assets [Line Items] | ||||
| Noncancelable operating lease expire date | Feb. 28, 2016 | |||