Accrued Liabilities - Product Maintenance and Warranty (Details) - Warranty $ in Thousands  | 
3 Months Ended | 9 Months Ended | 
|---|---|---|
| 
 Sep. 30, 2021  
USD ($) 
 | 
 Sep. 30, 2021  
USD ($) 
 | 
|
| Accrued Liabilities, Rollforward [Roll Forward] | ||
| Beginning Balance | $ 199 | $ 226 | 
| Additions for estimated future costs | 68 | 185 | 
| Incurred costs | (56) | (200) | 
| Closing Balance | 211 | 211 | 
| Current portion | 157 | 157 | 
| Long-term portion | 54 | 54 | 
| Total | $ 211 | $ 211 | 
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- Definition Accrued Liabilities, Rollforward [Roll Forward] No definition available. 
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- References No definition available. 
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- References No definition available. 
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- Definition Product Maintenance Warranty Liabilities, Current No definition available. 
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- References No definition available. 
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- Definition Product Maintenance Warranty Liabilities, Noncurrent No definition available. 
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- Details 
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