XML 15 R48.htm IDEA: XBRL DOCUMENT v3.3.0.814
Inventories (Details) - USD ($)
$ in Thousands
Sep. 30, 2015
Dec. 31, 2014
Inventory, Net [Abstract]    
Raw materials $ 78,066 $ 78,599
Work-in-process 49,597 33,941
Finished goods 18,412 19,969
Operating and other supplies 152,784 150,971
Total inventories $ 298,859 $ 283,480