Revenue - Additional Information (Detail) - USD ($) |
3 Months Ended | 12 Months Ended | |||
|---|---|---|---|---|---|
Jun. 30, 2014 |
Mar. 31, 2014 |
Dec. 31, 2015 |
Dec. 31, 2014 |
Dec. 31, 2013 |
|
| Revenue Recognition Milestone Method [Line Items] | |||||
| Revenue | $ 33,000 | $ 47,000 | $ 80,000 | $ 6,000 | |
| Material Transfer Agreement [Member] | |||||
| Revenue Recognition Milestone Method [Line Items] | |||||
| Revenue | $ 0 | 61,000 | $ 6,000 | ||
| Material Transfer Agreement One [Member] | |||||
| Revenue Recognition Milestone Method [Line Items] | |||||
| Revenue | $ 19,000 | ||||