Employee Benefit Plans (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Net periodic benefit cost [Abstract]
Total amount amortized out of accumulated other comprehensive income	$ 952	$ 3,410
Defined contribution plan expense	12,906	12,870
Post-Retirement Benefits [Member]
Net periodic benefit cost [Abstract]
Service cost	5	8
Interest cost	78	73
Prior service cost (credit)	3	3
Recognized actuarial loss	(18)	(8)
Net periodic (income)/expense	68	76
Qualified Plan [Member] | Defined benefit pension plans | U.S. Pension Plans, Defined Benefit [Member]
Net periodic benefit cost [Abstract]
Service cost	1,754	2,984
Interest cost	4,756	5,102
Expected return on plan assets	(8,534)	(10,211)
Prior service cost (credit)	76	87
Recognized actuarial loss	0	1,931
Transition obligation	0	0
Net periodic (income)/expense	(1,948)	(107)
Qualified Plan [Member] | Defined benefit pension plans | Foreign Pension Plans, Defined Benefit [Member]
Net periodic benefit cost [Abstract]
Service cost	1,545	1,577
Interest cost	1,241	1,378
Expected return on plan assets	(1,517)	(2,091)
Prior service cost (credit)	(58)	(115)
Recognized actuarial loss	816	803
Transition obligation	0	1
Net periodic (income)/expense	2,027	1,553
Nonqualified Plan [Member] | Supplemental Employee Retirement Plans, Defined Benefit [Member]
Net periodic benefit cost [Abstract]
Service cost	486	695
Interest cost	668	893
Prior service cost (credit)	703	963
Recognized actuarial loss	(570)	(255)
Net periodic (income)/expense	1,287	2,296
Discontinued Operations [Member] | Qualified Plan [Member] | Defined benefit pension plans | U.S. Pension Plans, Defined Benefit [Member]
Net periodic benefit cost [Abstract]
Net periodic (income)/expense	0	677
Discontinued Operations [Member] | Qualified Plan [Member] | Defined benefit pension plans | Foreign Pension Plans, Defined Benefit [Member]
Net periodic benefit cost [Abstract]
Net periodic (income)/expense	0	174
Discontinued Operations [Member] | Nonqualified Plan [Member] | Supplemental Employee Retirement Plans, Defined Benefit [Member]
Net periodic benefit cost [Abstract]
Net periodic (income)/expense	0	254
Continuing Operations [Member] | Qualified Plan [Member] | Defined benefit pension plans | U.S. Pension Plans, Defined Benefit [Member]
Net periodic benefit cost [Abstract]
Net periodic (income)/expense	(1,948)	(784)
Continuing Operations [Member] | Qualified Plan [Member] | Defined benefit pension plans | Foreign Pension Plans, Defined Benefit [Member]
Net periodic benefit cost [Abstract]
Net periodic (income)/expense	2,027	1,379
Continuing Operations [Member] | Nonqualified Plan [Member] | Supplemental Employee Retirement Plans, Defined Benefit [Member]
Net periodic benefit cost [Abstract]
Net periodic (income)/expense	$ 1,287	$ 2,042