Balance Sheet Details - Summary of Prepaid Expenses and Other Current Assets (Details) - USD ($) $ in Thousands |
Dec. 31, 2016 |
Dec. 31, 2015 |
|---|---|---|
| Organization, Consolidation and Presentation of Financial Statements [Abstract] | ||
| Prepaid trade shows | $ 217 | $ 246 |
| Prepaid insurance | 326 | 87 |
| Manufacturing deposits | 282 | 154 |
| Subscriptions | 297 | 128 |
| Other fees and services | 66 | 146 |
| Other current assets | 38 | 29 |
| Prepaid expense and other current assets | $ 1,226 | $ 790 |