Accumulated Other Comprehensive Income (Loss) (Components of OCI) (Details 1) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), before tax		$ (34,020)	$ 22,147	$ (23,511)	$ 43,546
Other Comprehensive Income (Loss), income tax		799	(5,008)	1,102	(8,125)
Other Comprehensive Income (Loss), Net of Tax		(33,221)	17,139	(22,409)	35,421
Foreign Currency Translation Adjustment [Member]
Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), before Reclassifications, before Tax		(31,167)	9,638	(19,603)	23,306
Other Comprehensive Income (Loss) before Reclassifications, Tax		0	0	0	0
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax		(31,167)	9,638	(19,603)	23,306
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax				0
Other Comprehensive Income (Loss), Net of Tax				(19,603)
Unrealized Gains (Losses) on Available-for-Sale Securities [Member]
Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), before Reclassifications, before Tax		0	13,976	0	23,534
Other Comprehensive Income (Loss) before Reclassifications, Tax		0	(5,591)	0	(9,414)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax		0	8,385	0	14,120
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax				0
Other Comprehensive Income (Loss), Net of Tax				0
Pension and Other Postretirement Plans [Member]
Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax				0
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax		(3,224)	(1,448)	(4,515)	(3,151)
Reclassification from AOCI, Current Period, Tax		869	579	1,217	1,260
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax		(2,355)	(869)	(3,298)	(1,891)
Other Comprehensive Income (Loss), before tax		(3,224)	(1,448)	(4,515)	(3,151)
Other Comprehensive Income (Loss), income tax		869	579	1,217	1,260
Other Comprehensive Income (Loss), Net of Tax		(2,355)	(869)	(3,298)	(1,891)
Net Prior Service Cost [Member]
Other Comprehensive Income (Loss) [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	[1]	70	120	146	240
Reclassification from AOCI, Current Period, Tax		(19)	(48)	(40)	(96)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax		51	72	106	144
Net Actuarial (Gain) Loss [Member]
Other Comprehensive Income (Loss) [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	[1]	(3,294)	(1,568)	(4,661)	(3,391)
Reclassification from AOCI, Current Period, Tax		888	627	1,257	1,356
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax		(2,406)	(941)	(3,404)	(2,035)
Cash Flow Hedge [Member]
Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax				526
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax				(34)
Other Comprehensive Income (Loss), before tax		371	(19)	607	(143)
Other Comprehensive Income (Loss), income tax		(70)	4	(115)	29
Other Comprehensive Income (Loss), Net of Tax		$ 301	$ (15)	$ 492	$ (114)

[1] These accumulated other comprehensive income components are components of net periodic pension and postretirement plan cost (see Note 12) and are included in non-operating pension and postretirement benefit income in the Company’s Condensed Consolidated Statements of Operations.