Accumulated Other Comprehensive Loss (AOCL) (Reclassifications) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Revenue	$ 891,898	$ 790,125	$ 2,525,658	$ 2,373,782
Selling, general and administrative	238,618	254,092	720,882	757,228
Income (loss) from continuing operations before taxes	11,327	(19,550)	(200,531)	18,761
Income tax provision	(554)	24,895	(7,540)	13,351
Net income (loss)	11,389	(3,125)	(200,423)	17,913
Reclassification out of Accumulated Other Comprehensive Loss | Cash flow hedges
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Revenue	(104)	(98)	(107)	(23)
Cost of sales	(6)	54	36	99
Income (loss) from continuing operations before taxes	(110)	(44)	(71)	76
Income tax provision	(27)	(11)	(18)	19
Net income (loss)	(83)	(33)	(53)	57
Reclassification out of Accumulated Other Comprehensive Loss | Available for sale securities
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Revenue	6,490	146	10,060	42
Selling, general and administrative	263	0	210	0
Income (loss) from continuing operations before taxes	6,753	146	10,270	42
Income tax provision	1,681	37	2,557	11
Net income (loss)	5,072	109	7,713	31
Reclassification out of Accumulated Other Comprehensive Loss | Pension and postretirement benefit plans
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income (loss) from continuing operations before taxes	(12,037)	(10,185)	(38,436)	(28,905)
Income tax provision	(2,875)	(2,633)	(9,027)	(7,406)
Net income (loss)	(9,162)	(7,552)	(29,409)	(21,499)
Reclassification out of Accumulated Other Comprehensive Loss | Transition credit
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Pension and postretirement benefit plans	1	2	3	5
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	(140)	(123)	(417)	(377)
Reclassification out of Accumulated Other Comprehensive Loss | Actuarial losses
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Pension and postretirement benefit plans	(10,990)	(8,587)	(32,923)	(25,858)
Reclassification out of Accumulated Other Comprehensive Loss | Settlements
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Pension and postretirement benefit plans	$ (908)	$ (1,477)	$ (5,099)	$ (2,675)