Balance Sheet Components - Accrued and Other Liabilities (Details) - USD ($) $ in Thousands |
Dec. 31, 2016 |
Dec. 31, 2015 |
|---|---|---|
| Accrued and Other Liabilities | ||
| Accrued clinical trial related | $ 1,617 | $ 376 |
| Accrued Manufacturing Expense | 955 | 12 |
| Personnel related | 526 | 305 |
| Deferred rent | 378 | 223 |
| Accrued legal and accounting | 255 | 314 |
| Accrued construction in progress costs | 101 | |
| Other accrued expenses | 313 | 164 |
| Accrued Liabilities and Other Liabilities, Total | $ 4,044 | $ 1,495 |