Pensions and Other Benefit Programs (Components of Net Periodic Benefit Cost (Income)) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Defined Benefit Pension Plans | United States
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 64	$ 16	$ 195	$ 69
Interest cost	10,353	12,719	31,842	39,077
Expected return on plan assets	(18,883)	(20,932)	(57,839)	(63,539)
Amortization of transition credit	0	0	0	0
Amortization of prior service (credit) cost	(15)	(15)	(45)	(45)
Amortization of net actuarial loss	9,366	7,972	28,643	24,367
Settlement	0	75	314	1,076
Net periodic benefit cost (income)	885	(165)	3,110	1,005
Contributions to benefit plans	1,161	2,061	4,020	5,959
Defined Benefit Pension Plans | Foreign
Defined Benefit Plan Disclosure [Line Items]
Service cost	346	422	1,055	1,220
Interest cost	2,961	3,548	8,929	10,473
Expected return on plan assets	(7,979)	(8,297)	(24,070)	(24,474)
Amortization of transition credit	0	(1)	0	(3)
Amortization of prior service (credit) cost	67	62	202	182
Amortization of net actuarial loss	2,340	2,092	7,065	6,156
Settlement	0	833	0	4,023
Net periodic benefit cost (income)	(2,265)	(1,341)	(6,819)	(2,423)
Contributions to benefit plans	355	445	9,379	9,013
Nonpension Postretirement Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Service cost	232	229	682	663
Interest cost	891	1,255	2,816	3,742
Expected return on plan assets	0	0	0	0
Amortization of transition credit	0	0	0	0
Amortization of prior service (credit) cost	32	93	97	280
Amortization of net actuarial loss	913	926	3,068	2,400
Settlement	0	0	0	0
Net periodic benefit cost (income)	2,068	2,503	6,663	7,085
Contributions to benefit plans	$ 2,642	$ 2,422	$ 9,542	$ 10,493