Inventories (Details) (USD $) In Thousands	Jun. 30, 2011	Dec. 31, 2010
Inventories
Raw materials and supplies	$ 270,756	$ 249,782
Work in process and finished goods	511,743	458,281
Total inventories, gross	782,499	708,063
Less inventory reserves	(42,123)	(34,200)
Total inventories, net	$ 740,376	$ 673,863