Inventory
 12 Months Ended
Dec. 31, 2016
Inventory.  
Inventory

4.  Inventory

 

Inventory as of December 31, 2016 and December 31, 2015 consists of the following (in thousands):

 

 

 

 

 

 

 

 

 

 

    

December 31, 2016

    

December 31, 2015

 

Raw materials and supplies

 

$
26,298

 

$
23,705

 

Work-in-process

 

 
1,865

 

 
5,567

 

Finished goods

 

 
1,777

 

 
3,480

 

 

 

$
29,940

 

$
32,752

 

 

Raw materials and supplies includes spare parts inventory held at service locations valued at approximately $3.3 million and $2.2 million as of December 31, 2016 and 2015, respectively.