Pensions and Other Benefit Programs (Components of Net Periodic Benefit Cost (Income)) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Defined Benefit Pension Plans | United States
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 105	$ 27	$ 131	$ 53
Interest cost	10,744	13,179	21,489	26,358
Expected return on plan assets	(19,478)	(21,303)	(38,956)	(42,607)
Amortization of transition credit	0	0	0	0
Amortization of prior service (credit) cost	(15)	(15)	(30)	(30)
Amortization of net actuarial loss	9,639	8,197	19,277	16,395
Settlement	314	612	314	1,001
Net periodic benefit cost (income)	1,309	697	2,225	1,170
Contributions to benefit plans	1,845	1,969	2,860	3,898
Defined Benefit Pension Plans | Foreign
Defined Benefit Plan Disclosure [Line Items]
Service cost	314	399	709	798
Interest cost	3,007	3,407	5,968	6,925
Expected return on plan assets	(8,107)	(7,969)	(16,091)	(16,177)
Amortization of transition credit	0	(1)	0	(2)
Amortization of prior service (credit) cost	68	59	135	120
Amortization of net actuarial loss	2,380	2,005	4,725	4,064
Settlement	0	3,190	0	3,190
Net periodic benefit cost (income)	(2,338)	1,090	(4,554)	(1,082)
Contributions to benefit plans	328	580	9,024	8,568
Nonpension Postretirement Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Service cost	226	217	450	434
Interest cost	964	1,242	1,925	2,487
Expected return on plan assets	0	0	0	0
Amortization of transition credit	0	0	0	0
Amortization of prior service (credit) cost	33	94	65	187
Amortization of net actuarial loss	1,077	738	2,155	1,474
Settlement	0	0	0	0
Net periodic benefit cost (income)	2,300	2,291	4,595	4,582
Contributions to benefit plans	$ 3,380	$ 3,616	$ 6,900	$ 8,071