Pension and Postretirement Benefits (Net Benefit Costs) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
U.S Defined Benefit Plans
Components of the net periodic cost for retirement and postretirement benefits
Service cost	$ 24,113	$ 22,981	$ 23,355
Interest cost	17,072	17,429	15,089
Expected return on plan assets	(24,185)	(21,985)	(19,952)
Settlement and other	0	0	(28)
Amortization of unrecognized prior service benefit	509	475	(87)
Amortization of unrecognized net loss	9,178	8,428	14,280
U.S. net pension expense	26,687	27,328	32,657
Non-U.S Defined Benefit Plans
Components of the net periodic cost for retirement and postretirement benefits
Service cost	7,832	6,857	6,819
Interest cost	11,770	14,576	13,486
Expected return on plan assets	(11,693)	(10,581)	(9,200)
Settlement and other	570	314	134
Amortization of unrecognized prior service benefit	(12)	0	0
Amortization of unrecognized net loss	4,949	6,962	6,650
U.S. net pension expense	13,416	18,128	17,889
Postretirement Medical Benefits
Components of the net periodic cost for retirement and postretirement benefits
Service cost	2	3	6
Interest cost	1,155	1,200	1,066
Amortization of unrecognized prior service benefit	122	0	0
Amortization of unrecognized net loss	(539)	(1,220)	(1,280)
U.S. net pension expense	$ 740	$ (17)	$ (208)