Inventories (Tables)
 6 Months Ended
Jun. 30, 2022
Inventory Disclosure [Abstract]  
Summary of Inventories
Inventories as of June 30, 2022 and December 31, 2021 consist of the following (in thousands):
 
 
  
June 30,
2022
 
  
December 31,
2021
 
Finished goods
    $ 5,397      $ 9,594  
Semi-finished goods and
work-in-process
      30,443        25,968  
Raw materials
      10,305        9,443  
Materials
in-transit
      229        95  
Less: inventory reserve
      (10,206 )       (5,730 ) 
    
 
 
     
 
 
  
Inventories, net
    $ 36,168      $ 39,370  
    
 
 
     
 
 
  
Changes in Inventory Reserve
Changes in inventory reserve for the three and six months ended June 30, 2022 and 2021 are as follows (in thousands):
 
 
  
Three Months
Ended
 
  
Six Months
Ended
 
  
Three Months
Ended
 
  
Six Months
Ended
 
 
  
 
 
  
 
 
  
 
 
  
 
 
 
  
June 30, 2022
 
  
June 30, 2021
 
Beginning balance
    $ (5,555 )     $ (5,730 )     $ (6,281 )     $ (5,901 ) 
Change in reserve
                                    
Inventory reserve charged to costs of sales
      (6,093 )       (7,700 )       (3,186 )       (5,350 ) 
Sale of previously reserved inventory
      872        2,324        1,343        1,977  
    
 
 
     
 
 
     
 
 
     
 
 
  
       (5,221 )       (5,376 )       (1,843 )       (3,373 ) 
Write off
      84        295        28        930  
Translation adjustments
      486        605        (5 )       243  
    
 
 
     
 
 
     
 
 
     
 
 
  
Ending balance
    $ (10,206 )     $ (10,206 )     $ (8,101 )     $ (8,101 )