Condensed Consolidated Statements of Income - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Income Statement [Abstract]
Sales	$ 108,323	$ 99,082
Cost of sales	76,024	75,871
Gross profit	32,299	23,211
Selling, general and administrative expenses	11,799	9,503
Operating income	20,500	13,708
Interest expense, net and other	(458)	(642)
Income before income taxes	20,042	13,066
Income tax expense	4,615	3,224
Net income	15,427	9,842
Income attributable to participating securities	146	66
Net income attributable to common shareholders and used in Earnings Per Share calculation	$ 15,281	$ 9,776
Share information:
Basic and diluted weighted average common shares (in shares)	16,928,003	17,013,925
Basic and diluted earnings per common share (in USD per share)	$ 0.90	$ 0.57

The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 924
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 11.L)
-URI http://asc.fasb.org/extlink&oid=6472922&loc=d3e499488-122856

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.2(a),(d))
-URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227