| Property and Equipment (Narrative) (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
| Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020 | |
| Property and Equipment | ||||
| Depreciation expense | $ 600 | $ 400 | $ 1,512 | $ 1,223 | 
| X | ||||||||||
| 
- Definition The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
 | 
| X | ||||||||||
| 
- References No definition available. 
 |