Accumulated Other Comprehensive Income (Loss) - Reclassifications Out of Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Selling, general and administrative expenses	$ 260,752	$ 254,969	$ 776,135	$ 750,266
Tax (benefit) expense	19,761	20,724	54,220	48,396
Total reclassifications for the period, net of tax	(29,554)	(30,196)	(80,678)	(70,987)
Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Selling, general and administrative expenses	5,133	4,529	15,398	13,587
Tax (benefit) expense	(1,997)	(1,762)	(5,990)	(5,286)
Total reclassifications for the period, net of tax	3,136	2,767	9,408	8,301
Actuarial Losses Recognized | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Selling, general and administrative expenses	5,573	4,968	16,718	14,904
Tax (benefit) expense	(2,168)	(1,933)	(6,503)	(5,798)
Total reclassifications for the period, net of tax	3,405	3,035	10,215	9,106
Prior Service Costs Recognized | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Selling, general and administrative expenses	(440)	(439)	(1,320)	(1,317)
Tax (benefit) expense	171	171	513	512
Total reclassifications for the period, net of tax	$ (269)	$ (268)	$ (807)	$ (805)