Fair Value Measurements - Contingent Consideration (Details) - USD ($) $ in Thousands |
9 Months Ended | ||
|---|---|---|---|
Sep. 30, 2018 |
Sep. 30, 2017 |
Dec. 31, 2017 |
|
| Financial Liabilities | |||
| Balance, contingent consideration | $ (748) | $ (1,195) | |
| CEMP change in fair value measurement | 4 | $ 25 | |
| CEMP year 3 earn-out payment | 443 | ||
| Transfers between levels | $ 0 | $ 0 | |