Consolidated Statements of Income - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Income Statement [Abstract]
Net Sales	$ 115,788	$ 137,483
Cost of sales	82,631	94,536
Gross profit	33,157	42,947
Selling, general and administrative expenses	14,696	15,214
(Gain) loss on disposal of assets	0	(62)
Income from operations	18,461	27,795
Interest income, net	3	61
Other income (expense), net	17	(27)
Income before taxes	18,481	27,829
Income tax provision	2,105	5,976
Net income	$ 16,376	$ 21,853
Earnings per share:
Basic (usd per share)	$ 0.31	$ 0.42
Diluted (usd per share)	$ 0.30	$ 0.41
Weighted average shares outstanding:
Basic (in shares)	52,293,464	52,071,839
Diluted (in shares)	53,814,644	52,871,419