Net Periodic Benefit Cost (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
United States Pension Plans of US Entity, Defined Benefit [Member]
Components of Net periodic pension cost for the Company's defined benefit pension plans and U.S. post-retirement medical plan
Service cost, net	$ 114,000	$ 83,000	$ 228,000	$ 166,000
Interest cost on projected benefit obligations	1,523,000	1,606,000	3,046,000	3,212,000
Expected return on plan assets	(1,741,000)	(1,875,000)	(3,483,000)	(3,750,000)
Net amortization and deferral	0	0	0	0
Recognition of actuarial losses/(gains)	1,916,000	1,276,000	3,832,000	2,552,000
Net periodic pension cost/(credit)	1,812,000	1,090,000	3,623,000	2,180,000
Net Periodic Benefit Cost (Textuals) [Abstract]
Defined Benefit Plan, Estimated Future Employer Contributions in Current Fiscal Year	3,700,000		3,700,000
Foreign Pension Plans, Defined Benefit [Member]
Components of Net periodic pension cost for the Company's defined benefit pension plans and U.S. post-retirement medical plan
Service cost, net	3,588,000	3,590,000	7,226,000	6,947,000
Interest cost on projected benefit obligations	5,535,000	6,282,000	11,139,000	12,196,000
Expected return on plan assets	(8,141,000)	(8,704,000)	(16,375,000)	(16,852,000)
Net amortization and deferral	(353,000)	(378,000)	(710,000)	(727,000)
Recognition of actuarial losses/(gains)	609,000	291,000	1,223,000	576,000
Net periodic pension cost/(credit)	1,238,000	1,081,000	2,503,000	2,140,000
Net Periodic Benefit Cost (Textuals) [Abstract]
Defined Benefit Plan, Estimated Future Employer Contributions in Current Fiscal Year	20,600,000		20,600,000
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member]
Components of Net periodic pension cost for the Company's defined benefit pension plans and U.S. post-retirement medical plan
Service cost, net	83,000	76,000	166,000	152,000
Interest cost on projected benefit obligations	135,000	183,000	270,000	366,000
Expected return on plan assets	0	0	0	0
Net amortization and deferral	0	0	0	0
Recognition of actuarial losses/(gains)	(188,000)	(173,000)	(377,000)	(346,000)
Net periodic pension cost/(credit)	30,000	86,000	59,000	172,000
Net Periodic Benefit Cost (Textuals) [Abstract]
Defined Benefit Plan, Estimated Future Employer Contributions in Current Fiscal Year	$ 1,100,000		$ 1,100,000