Inventory, net (Tables)
 12 Months Ended
Dec. 31, 2016
Inventory Disclosure [Abstract]  
Schedule of Inventory, Net of Reserves
Inventory, net of reserves, consisted of the following amounts (in thousands):
 
December 31,
 
2016
 
2015
Parts and supplies
$
104,897

 
$
133,558

Work in progress
32,167

 
41,184

Finished goods
20,452

 
33,339

Inventory, net
$
157,516

 
$
208,081