Accumulated Other Comprehensive Loss (Reclassifications) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Revenue	$ 915,197	$ 796,268
Selling, general and administrative	(238,102)	(248,633)
Loss from continuing operations before taxes	(41,647)	(228,577)
Income tax provision	13,992	10,030
Net loss	(31,541)	(208,483)
Reclassification out of Accumulated Other Comprehensive Loss | Cash flow hedges
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Revenue	126	61
Cost of sales	(58)	10
Loss from continuing operations before taxes	68	71
Income tax provision	17	17
Net loss	51	54
Reclassification out of Accumulated Other Comprehensive Loss | Available for sale securities
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Revenue	(1)	284
Selling, general and administrative	42	0
Loss from continuing operations before taxes	41	284
Income tax provision	10	71
Net loss	31	213
Reclassification out of Accumulated Other Comprehensive Loss | Pension and postretirement benefit plans
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Loss from continuing operations before taxes	(13,145)	(11,520)
Income tax provision	(3,208)	(2,650)
Net loss	(9,937)	(8,870)
Reclassification out of Accumulated Other Comprehensive Loss | Transition credit
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Pension and postretirement benefit plans	0	1
Reclassification out of Accumulated Other Comprehensive Loss | Prior service costs
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Pension and postretirement benefit plans	(84)	(139)
Reclassification out of Accumulated Other Comprehensive Loss | Actuarial losses
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Pension and postretirement benefit plans	(13,061)	(10,993)
Reclassification out of Accumulated Other Comprehensive Loss | Settlements
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Pension and postretirement benefit plans	$ 0	$ (389)