Benefit Plans Benefit Plans (Detail 2) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items]
Assets for Plan Benefits, Defined Benefit Plan	$ 46,014	$ 40,493
Liability, Defined Benefit Plan, Current	5,425	5,489
Liability, Defined Benefit Plan, Noncurrent	174,121	178,944
Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, before Tax	321,254	314,324
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), after Reclassification Adjustment, before Tax	187,722	170,384
Pension Plan [Member] | Foreign Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Assets for Plan Benefits, Defined Benefit Plan	46,014	40,493
Liability, Defined Benefit Plan, Current	4,884	4,990
Liability, Defined Benefit Plan, Noncurrent	137,815	145,766
Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, before Tax	260,820	254,870
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), after Reclassification Adjustment, before Tax	164,135	144,607
Pension Plan [Member] | Domestic Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Assets for Plan Benefits, Defined Benefit Plan	0	0
Liability, Defined Benefit Plan, Current	110	88
Liability, Defined Benefit Plan, Noncurrent	34,551	30,916
Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, before Tax	61,344	61,819
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), after Reclassification Adjustment, before Tax	26,683	30,815
Other Postretirement Benefits Plan [Member] | Domestic Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Assets for Plan Benefits, Defined Benefit Plan	0	0
Liability, Defined Benefit Plan, Current	431	411
Liability, Defined Benefit Plan, Noncurrent	1,755	2,262
Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, before Tax	(910)	(2,365)
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), after Reclassification Adjustment, before Tax	$ (3,096)	$ (5,038)