Accumulated Other Comprehensive Income (Loss) (Reclassifications out of AOCI) (Details 3) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Other income, net		$ (4,069)	$ (19,000)	$ (4,918)	$ (34,096)
Interest expense		9,035	7,971	17,164	15,919
Provision for Income Taxes		23,900	23,800	26,600	46,200
Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Income Net of Tax		(836)	(2,465)	(1,833)	(3,281)
Foreign Currency Translation Adjustment [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Reclassifications, net of tax				0
Unrealized Gain on Available-for-Sale Securities [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Reclassifications, before tax		0	(4,502)	0	(6,256)
Provision for Income Tax		0	1,801	0	2,502
Reclassifications, net of tax		0	(2,701)	0	(3,754)
Unrealized Gain on Available-for-Sale Securities [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Other income, net		0	(4,502)	0	(6,256)
Provision for Income Taxes		0	1,801	0	2,502
Income Net of Tax		0	(2,701)	0	(3,754)
Pension and Other Postretirement Plans [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Reclassifications, before tax		(1,448)	394	(3,151)	788
Provision for Income Tax		579	(158)	1,260	(315)
Reclassifications, net of tax		(869)	236	(1,891)	473
Net Prior Service Cost [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Reclassifications, before tax	[1]	120	105	240	209
Provision for Income Tax		(48)	(43)	(96)	(84)
Reclassifications, net of tax		72	62	144	125
Net Actuarial (Gain) Loss [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Reclassifications, before tax	[1]	(1,568)	289	(3,391)	579
Provision for Income Tax		627	(115)	1,356	(231)
Reclassifications, net of tax		(941)	174	(2,035)	348
Cash Flow Hedge [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Reclassifications, net of tax				58
Cash Flow Hedge [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Interest expense		41	0	72	0
Provision for Income Taxes		(8)	0	(14)	0
Income Net of Tax		$ 33	$ 0	$ 58	$ 0

[1] These accumulated other comprehensive income components are included in the computation of net periodic pension and postretirement plan cost (see Note 8).