Equipment - Equipment (Detail) - USD ($) $ in Thousands |
Dec. 31, 2016 |
Dec. 31, 2015 |
|---|---|---|
| Property, Plant and Equipment [Line Items] | ||
| Equipment, Gross | $ 10,201 | $ 8,923 |
| Accumulated depreciation | (7,596) | (7,788) |
| Equipment, net | 2,605 | 1,135 |
| Laboratory Equipment [Member] | ||
| Property, Plant and Equipment [Line Items] | ||
| Equipment, Gross | 6,196 | 6,232 |
| Office Equipment and Leasehold Improvements [Member] | ||
| Property, Plant and Equipment [Line Items] | ||
| Equipment, Gross | 3,040 | $ 2,691 |
| Process Development Equipment Not Yet in Service [Member] | ||
| Property, Plant and Equipment [Line Items] | ||
| Equipment, Gross | $ 965 |