Pensions and Other Benefit Programs (Components of Net Periodic Benefit Cost (Income)) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Defined Benefit Pension Plans | United States
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 23	$ 34	$ 69	$ 98
Interest cost	15,363	17,122	46,087	51,488
Expected return on plan assets	(25,281)	(24,369)	(75,815)	(73,287)
Amortization of transition credit	0	0	0	0
Amortization of prior service (credit) cost	(15)	(15)	(45)	(45)
Amortization of net actuarial loss	7,851	7,229	23,555	21,725
Settlement/Curtailment	796	0	796	0
Net periodic benefit cost (income)	(1,263)	1	(5,353)	(21)
Contributions to benefit plans	2,479	1,792	5,674	4,691
Defined Benefit Pension Plans | Foreign
Defined Benefit Plan Disclosure [Line Items]
Service cost	567	587	1,731	1,688
Interest cost	4,434	4,809	13,721	13,993
Expected return on plan assets	(8,730)	(8,214)	(27,045)	(23,956)
Amortization of transition credit	(2)	(2)	(5)	(6)
Amortization of prior service (credit) cost	(18)	(18)	(54)	(53)
Amortization of net actuarial loss	1,807	2,055	5,590	5,981
Settlement/Curtailment	0	0	0	0
Net periodic benefit cost (income)	(1,942)	(783)	(6,062)	(2,353)
Contributions to benefit plans	661	1,000	10,640	11,391
Nonpension Postretirement Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Service cost	298	438	1,109	1,290
Interest cost	1,676	1,780	4,888	5,321
Expected return on plan assets	0	0	0	0
Amortization of transition credit	0	0	0	0
Amortization of prior service (credit) cost	112	74	287	223
Amortization of net actuarial loss	338	905	2,153	2,693
Settlement/Curtailment	339	0	339	0
Net periodic benefit cost (income)	2,763	3,197	8,776	9,527
Contributions to benefit plans	$ 4,442	$ 4,009	$ 13,552	$ 13,027