Changes in Accumulated Other Comprehensive Income (Loss) by Component - Amount Reclassified from Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest expense	$ (4,027)	$ (3,701)	$ (12,443)	$ (11,924)
Net sales	325,059	269,059	947,846	835,266
Tax benefit	(10,602)	(12,137)	(26,501)	(30,390)
Net income	27,863	15,358	71,736	45,658
Amount Reclassified from Accumulated Other Comprehensive Income (Loss)
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net income	(3,345)	(2,928)	(10,178)	(9,258)
Amount Reclassified from Accumulated Other Comprehensive Income (Loss) | (Losses)/gains on cash flow hedges
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest expense	(468)	(449)	(1,377)	(866)
Net sales	219	237	517	(213)
Income before income taxes	(249)	(212)	(860)	(1,079)
Tax benefit	75	85	233	221
Net income	(174)	(127)	(627)	(858)
Amount Reclassified from Accumulated Other Comprehensive Income (Loss) | Amortization of prior service costs
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income before income taxes	(90)	(134)	(270)	(301)
Amount Reclassified from Accumulated Other Comprehensive Income (Loss) | Amortization of actuarial losses
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income before income taxes	(4,053)	(3,511)	(12,199)	(10,175)
Amount Reclassified from Accumulated Other Comprehensive Income (Loss) | Pension and Other Postretirement Benefit Items
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income before income taxes	(4,143)	(3,645)	(12,469)	(10,960)
Curtailment loss			0	(484)
Tax benefit	972	844	2,918	2,560
Net income	$ (3,171)	$ (2,801)	$ (9,551)	$ (8,400)