Summary of Business and Significant Accounting Principles - Estimated Useful Lives (Details) |
12 Months Ended |
|---|---|
Dec. 31, 2019 | |
| Buildings | Maximum | |
| Property, Plant and Equipment [Line Items] | |
| Property, plant and equipment, useful life | 39 years |
| Buildings | Minimum | |
| Property, Plant and Equipment [Line Items] | |
| Property, plant and equipment, useful life | 15 years |
| Software | Maximum | |
| Property, Plant and Equipment [Line Items] | |
| Property, plant and equipment, useful life | 6 years |
| Software | Minimum | |
| Property, Plant and Equipment [Line Items] | |
| Property, plant and equipment, useful life | 3 years |
| Equipment | |
| Property, Plant and Equipment [Line Items] | |
| Property, plant and equipment, useful life | 5 years |
| Vehicles and prototypes | Maximum | |
| Property, Plant and Equipment [Line Items] | |
| Property, plant and equipment, useful life | 5 years |
| Vehicles and prototypes | Minimum | |
| Property, Plant and Equipment [Line Items] | |
| Property, plant and equipment, useful life | 3 years |