Accumulated Other Comprehensive Income (Reclassifications) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total Revenue from sales and services (ASC 606)	$ 640,003		$ 1,293,790
Interest expense, net	(29,623)	$ (27,600)	(60,476)	$ (53,276)
Selling, general and administrative	(282,456)	(283,073)	(577,894)	(573,645)
Income from continuing operations before taxes	53,464	42,251	114,753	126,757
(Provision) benefit from income taxes	(6,458)	(790)	(22,721)	(27,872)
Net income	48,214	48,901	101,727	114,034
Reclassification out of Accumulated Other Comprehensive Loss \| Cash flow hedges
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total Revenue from sales and services (ASC 606)	79	34	76	6
Cost of sales	(1)	36	(85)	148
Interest expense, net	(507)	(507)	(1,014)	(1,014)
Income from continuing operations before taxes	(429)	(437)	(1,023)	(860)
(Provision) benefit from income taxes	110	170	261	336
Net income	(319)	(267)	(762)	(524)
Reclassification out of Accumulated Other Comprehensive Loss \| Available for sale securities
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest expense, net	214	(117)	190	(226)
(Provision) benefit from income taxes	(54)	44	(48)	84
Net income	160	(73)	142	(142)
Reclassification out of Accumulated Other Comprehensive Loss \| Pension and postretirement benefit plans
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income from continuing operations before taxes	(10,432)	(10,066)	(21,408)	(20,291)
(Provision) benefit from income taxes	2,564	3,442	5,368	6,956
Net income	(7,868)	(6,624)	(16,040)	(13,335)
Reclassification out of Accumulated Other Comprehensive Loss \| Transition credit
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Selling, general and administrative	2	2	3	4
Reclassification out of Accumulated Other Comprehensive Loss \| Prior service costs
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Selling, general and administrative	(55)	(42)	(109)	(83)
Reclassification out of Accumulated Other Comprehensive Loss \| Actuarial losses
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Selling, general and administrative	$ (10,379)	$ (10,026)	$ (21,302)	$ (20,212)

The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

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