Postretirement Benefit Plans (Details Textual) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Postretirement benefit plan (Textual) [Abstract]
Balance of the trust assets	$ 1,504,000		$ 1,504,000
U.S Plans [Member]
Postretirement benefit plan (Textual) [Abstract]
Company's expected contribution to qualified plan	5,418,000		5,418,000
Contribution to the qualified plans			5,418,000
Expected payment related to Nonqualified plan	268,000		268,000
Payment related to the non-qualified plans			172,000
U.S Plans [Member] | Previously disclosed [Member]
Postretirement benefit plan (Textual) [Abstract]
Company's expected contribution to qualified plan	6,698,000		6,698,000
U.K Plan [Member]
Postretirement benefit plan (Textual) [Abstract]
Company's expected contribution to qualified plan	940,000		940,000
Contribution to the qualified plans			732,000
Retirement Savings Plans [Member]
Postretirement benefit plan (Textual) [Abstract]
Defined contribution plan expense	1,072,000	1,027,000	3,184,000	2,982,000
Profit Sharing Plan [Member]
Postretirement benefit plan (Textual) [Abstract]
Defined contribution plan expense	$ 1,484,000	$ 1,064,000	$ 4,365,000	$ 3,644,000