Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Income Statement [Abstract]
Net sales	$ 231,502	$ 194,551	$ 652,545	$ 580,575
Cost of sales	146,538	112,120	385,479	345,334
Gross profit	84,964	82,431	267,066	235,241
Selling, general and administrative expenses	28,027	27,409	91,598	93,281
Income from operations	56,937	55,022	175,468	141,960
Interest income, net	(208)	(744)	(801)	(801)
Income before income taxes	57,145	55,766	176,269	142,761
Provision for income taxes	14,435	13,790	43,938	33,520
Net income	$ 42,710	$ 41,976	$ 132,331	$ 109,241
Basic earnings per common share	$ 0.37	$ 0.36	$ 1.14	$ 0.94
Basic weighted average common shares outstanding	115,773,030	116,802,366	115,921,463	116,952,860
Diluted earnings per common share	$ 0.37	$ 0.36	$ 1.14	$ 0.93
Diluted weighted average common shares outstanding	116,134,623	117,211,452	116,280,807	117,413,920
Comprehensive income	$ 42,710	$ 41,976	$ 132,331	$ 109,241