Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Income Statement [Abstract]
Net sales	$ 179,571	$ 171,207
Cost of sales	110,206	94,494
Gross profit	69,365	76,713
Selling, general and administrative expenses	30,166	28,959
Income from operations	39,199	47,754
Interest (income) expense, net	(56)	229
Income before income taxes	39,255	47,525
Provision for income taxes	7,700	10,415
Net income	$ 31,555	$ 37,110
Basic earnings per common share	$ 0.54	$ 0.63
Basic weighted average common shares outstanding	58,543,478	58,855,156
Diluted earnings per common share	$ 0.54	$ 0.63
Diluted weighted average common shares outstanding	58,829,177	59,199,622
Comprehensive income	$ 31,555	$ 37,110