Concentrations - Narrative (Details) - Customer Concentration Risk |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2018 |
Jun. 30, 2017 |
Jun. 30, 2018 |
Jun. 30, 2017 |
|
| One additional OEM customer | Sales Revenue, Net | ||||
| Concentration Risk [Line Items] | ||||
| Concentration risk, percentage | 10.00% | |||
| Supplier One | Material Purchases | ||||
| Concentration Risk [Line Items] | ||||
| Concentration risk, percentage | 43.00% | 56.00% | ||
| Supplier Two | Material Purchases | ||||
| Concentration Risk [Line Items] | ||||
| Concentration risk, percentage | 11.00% | 10.00% | ||
| Supplier Three | Material Purchases | ||||
| Concentration Risk [Line Items] | ||||
| Concentration risk, percentage | 35.00% | 28.00% | ||
| Supplier Four | Material Purchases | ||||
| Concentration Risk [Line Items] | ||||
| Concentration risk, percentage | 15.00% | 14.00% | ||
| Supplier Five | Material Purchases | ||||
| Concentration Risk [Line Items] | ||||
| Concentration risk, percentage | 14.00% | 11.00% | ||