Intangible Assets (Details) - USD ($) $ in Thousands |
12 Months Ended | |
|---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
|
| Finite-Lived Intangible Assets [Line Items] | ||
| Gross Carrying Amount | $ 11,197 | $ 11,197 |
| Accumulated Amortization | (6,625) | (4,417) |
| Net Carrying Amount | $ 4,572 | 6,780 |
| Amortization expense | $ 2,200 | |
| Software and technology | ||
| Finite-Lived Intangible Assets [Line Items] | ||
| Weighted Average Amortization Period (Years) | 1 year | 2 years |
| Gross Carrying Amount | $ 4,108 | $ 4,108 |
| Accumulated Amortization | (3,081) | (2,054) |
| Net Carrying Amount | $ 1,027 | $ 2,054 |
| Customer Relationships | ||
| Finite-Lived Intangible Assets [Line Items] | ||
| Weighted Average Amortization Period (Years) | 3 years | 4 years |
| Gross Carrying Amount | $ 7,089 | $ 7,089 |
| Accumulated Amortization | (3,544) | (2,363) |
| Net Carrying Amount | $ 3,545 | $ 4,726 |