Inventories (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Inventory Disclosure [Abstract]
Raw materials	$ 25,803	$ 30,986
Work in Process	6,408	6,189
Supplies and service parts	44,323	33,760
Finished products	24,618	26,992
Inventory at FIFO cost	101,152	97,927
Excess of FIFO cost over LIFO cost	(12,328)	(13,100)
Total inventory, net	$ 88,824	$ 84,827