Consolidated Statements of Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Income Statement [Abstract]
Net Sales	$ 138,571	$ 134,772	$ 398,235	$ 397,851
Cost of sales	102,552	93,924	286,952	275,925
Gross profit	36,019	40,848	111,283	121,926
Selling, general and administrative expenses	15,897	14,716	47,488	45,869
Gain on disposal of assets	(15)	1	(15)	(61)
Income from operations	20,137	26,131	63,810	76,118
Interest (expense) income, net	(10)	10	(11)	90
Other (expense) income, net	(19)	15	37	20
Income before taxes	20,108	26,156	63,836	76,228
Income tax provision	4,527	5,696	11,264	16,111
Net income	$ 15,581	$ 20,460	$ 52,572	$ 60,117
Earnings per share:
Basic (usd per share)	$ 0.30	$ 0.39	$ 1.00	$ 1.15
Diluted (usd per share)	0.29	0.38	0.98	1.14
Cash dividends declared per common share (in dollars per share)	$ 0	$ 0	$ 0.19	$ 0.19
Weighted average shares outstanding:
Basic (in shares)	52,420,711	52,260,551	52,392,300	52,174,705
Diluted (in shares)	53,546,513	53,151,295	53,664,997	52,955,049