Inventories (Schedule of Inventories) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Inventories [Abstract]
Finished goods	$ 69,219	$ 71,758
Work-in-process	10,643	8,004
Raw materials	20,916	19,885
Total inventories at current costs	100,778	99,647
Less: LIFO reserve	(9,850)	(10,183)
Inventory	$ 90,928	$ 89,464