Segment Geographic and Market Information (Details 1) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011		Dec. 31, 2010		Dec. 31, 2009
Geographic information
Sales to unaffiliated customers shipped	$ 943,796	[1]	$ 826,277	[1]	$ 687,485	[1]
Operating profit from sales	86,086	[1]	69,012	[1]	49,344	[1]
Account receivable	204,419	[1]	189,772	[1]	147,255	[1]
Property, plant, equipment, and mineral rights and reserves	273,568	[1]	271,680	[1]	248,351	[1]
Identifiable assets	849,142	[1]	807,255	[1]	746,835	[1]
Americas [Member]
Geographic information
Sales to unaffiliated customers shipped	590,074	[1]	516,852	[1]	438,194	[1]
Operating profit from sales	57,534	[1]	45,800	[1]	26,742	[1]
Account receivable	112,325	[1]	105,979	[1]	76,598	[1]
Property, plant, equipment, and mineral rights and reserves	116,020	[1]	107,670	[1]	108,405	[1]
Identifiable assets	420,427	[1]	428,689	[1]	453,599	[1]
EMEA [Member]
Geographic information
Sales to unaffiliated customers shipped	220,100	[1]	185,591	[1]	167,482	[1]
Operating profit from sales	10,236	[1]	5,625	[1]	11,848	[1]
Account receivable	51,875	[1]	46,518	[1]	40,951	[1]
Property, plant, equipment, and mineral rights and reserves	108,688	[1]	114,263	[1]	92,541	[1]
Identifiable assets	289,416	[1]	265,459	[1]	211,100	[1]
Asia Pacific [Member]
Geographic information
Sales to unaffiliated customers shipped	133,622	[1]	123,834	[1]	81,809	[1]
Operating profit from sales	18,316	[1]	17,587	[1]	10,754	[1]
Account receivable	40,219	[1]	37,275	[1]	29,706	[1]
Property, plant, equipment, and mineral rights and reserves	48,860	[1]	49,747	[1]	47,405	[1]
Identifiable assets	$ 139,299	[1]	$ 113,107	[1]	$ 82,136	[1]

[1] Restated