Condensed Consolidated Statements of Income - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Income Statement [Abstract]
Sales	$ 99,082	$ 89,096
Cost of sales	75,871	72,436
Gross profit	23,211	16,660
Selling, general and administrative expenses	9,503	8,147
Operating income	13,708	8,513
Interest expense, net and other	(642)	(252)
Income before income taxes	13,066	8,261
Income tax expense (benefit)	3,224	(1,459)
Net income	9,842	9,720
Income attributable to participating securities	66	66
Net income attributable to common shareholders and used in earnings per share calculation	$ 9,776	$ 9,654
Share information:
Basic and diluted weighted average common shares (in shares)	17,013,925	16,967,631
Basic and diluted earnings per common share (in dollars per share)	$ 0.57	$ 0.57