Net Periodic Benefit Cost (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Components of Net periodic pension cost for the Company's defined benefit pension plans and U.S. post-retirement medical plan
Service cost, net	$ 4,228	$ 4,546
Interest cost on projected benefit obligations	7,142	6,423
Expected return on plan assets	(11,681)	(10,480)
Net amortization and deferral	(1,235)	(972)
Recognition of actuarial losses/(gains)	1,947	3,544
Net periodic pension cost/(credit)	401	3,061
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	223	123
Interest cost on projected benefit obligations	1,599	1,439
Expected return on plan assets	(2,137)	(1,788)
Net amortization and deferral	0	0
Recognition of actuarial losses/(gains)	1,200	1,945
Net periodic pension cost/(credit)	885	1,719
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	3,962	4,369
Interest cost on projected benefit obligations	5,483	4,883
Expected return on plan assets	(9,544)	(8,692)
Net amortization and deferral	(1,040)	(994)
Recognition of actuarial losses/(gains)	1,106	1,846
Net periodic pension cost/(credit)	(33)	1,412
Net Periodic Benefit Cost (Textuals) [Abstract]
Defined Benefit Plan, Estimated Future Employer Contributions in Current Fiscal Year	21,800
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	43	54
Interest cost on projected benefit obligations	60	101
Expected return on plan assets	0	0
Net amortization and deferral	(195)	22
Recognition of actuarial losses/(gains)	(359)	(247)
Net periodic pension cost/(credit)	(451)	(70)
Net Periodic Benefit Cost (Textuals) [Abstract]
Defined Benefit Plan, Estimated Future Employer Contributions in Current Fiscal Year	$ 500