Commitments and Contingencies - Additional Information (Detail) - USD ($) $ in Thousands |
12 Months Ended | |||
|---|---|---|---|---|
Feb. 12, 2014 |
Dec. 31, 2015 |
Dec. 31, 2014 |
Dec. 31, 2013 |
|
| Commitments And Contingencies [Line Items] | ||||
| Non-cancelable operating leases expiration | June 2017 and June 2018 | |||
| Rental expense | $ 778 | $ 649 | $ 448 | |
| Incept [Member] | Common Stock [Member] | ||||
| Commitments And Contingencies [Line Items] | ||||
| Common stock, shares issued | 189,393 | |||