Inventories (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Inventories [Abstract]
Raw materials and parts	$ 149,471	$ 141,967
Work-in-process	132,305	113,859
Finished goods	82,419	104,879
Used equipment	25,309	24,071
Total	$ 389,504	$ 384,776