Intangible Assets - Future Amortization (Details) - USD ($) $ in Thousands |
Mar. 31, 2018 |
Dec. 31, 2017 |
|---|---|---|
| Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract] | ||
| 2018 | $ 601 | |
| 2019 | 352 | |
| 2020 | 259 | |
| 2021 | 124 | |
| 2022 | 61 | |
| Net Carrying Value | $ 1,397 | $ 1,725 |