Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Income Statement [Abstract]
Net sales	$ 140,194	$ 106,168	$ 442,941	$ 384,294
Cost of sales	84,910	76,223	250,473	235,312
Gross profit	55,284	29,945	192,468	148,982
Selling, general and administrative expenses	24,919	19,379	75,409	64,786
Income from operations	30,365	10,566	117,059	84,196
Interest expense, net	59	77	515	1,108
Income before income taxes	30,306	10,489	116,544	83,088
Provision for income taxes	10,208	2,702	39,715	27,871
Net income	$ 20,098	$ 7,787	$ 76,829	$ 55,217
Basic earnings per common share	$ 0.68	$ 0.27	$ 2.61	$ 1.88
Basic weighted average common shares outstanding	29,404,049	29,295,284	29,385,722	29,419,958
Diluted earnings per common share	$ 0.68	$ 0.26	$ 2.60	$ 1.86
Diluted weighted average common shares outstanding	29,578,216	29,516,718	29,563,497	29,635,796
Comprehensive income	$ 20,098	$ 7,787	$ 76,829	$ 55,217