Acquisitions - Business Acquisition Pro Forma Information (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 29, 2018	Sep. 29, 2018
Business Combinations [Abstract]
Net sales	$ 439,191	$ 1,332,900
Income before income taxes	71,737	228,503
Net income	$ 56,060	$ 179,264
Net income per share — basic (in dollars per share)	$ 2.23	$ 7.17
Net income per share — diluted (in dollars per share)	$ 2.18	$ 7.16