Changes in Accumulated Other Comprehensive Income (Loss) by Component (Details 2) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest expense	$ (3,892)	$ (3,349)
Net sales	366,660	341,802
Income before income taxes	50,978	52,376
Tax benefit	(12,160)	(14,073)
Total reclassifications in the period	38,818	38,303
Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total reclassifications in the period	(2,640)	(1,535)
Reclassification out of Accumulated Other Comprehensive Income [Member] | Gains and Losses on Cash Flow Hedges
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income before income taxes	(308)	(83)
Tax benefit	69	27
Income from continuing operations	(239)	(56)
Reclassification out of Accumulated Other Comprehensive Income [Member] | Gains and Losses on Cash Flow Hedges | Interest Rate Contract [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest expense	(82)	(53)
Reclassification out of Accumulated Other Comprehensive Income [Member] | Gains and Losses on Cash Flow Hedges | Foreign Exchange Contract [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net sales	(226)	(30)
Reclassification out of Accumulated Other Comprehensive Income [Member] | Pension and Other Postretirement Benefit Items
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income before income taxes	(3,117)	(2,380)
Tax benefit	716	901
Income from continuing operations	(2,401)	(1,479)
Amortization of prior-service credits, net	(146)	(92)
Amortization of actuarial losses	(2,971)	(2,549)
Settlement gain	$ 0	$ 261