Condensed Consolidated Statements of Net Income (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 29, 2018	Sep. 30, 2017	Sep. 29, 2018	Sep. 30, 2017
Income Statement [Abstract]
Net sales	$ 439,191	$ 317,889	$ 1,316,187	$ 916,685
Cost of sales	259,597	184,238	817,983	536,776
Gross profit	179,594	133,651	498,204	379,909
Selling, general, and administrative expenses	69,782	56,759	220,540	156,899
Research and development expenses	20,454	11,991	65,742	36,872
Amortization of intangibles	13,130	6,292	38,501	18,407
Total operating expenses	103,366	75,042	324,783	212,178
Operating income	76,228	58,609	173,421	167,731
Interest expense	5,775	3,467	16,980	9,868
Foreign exchange loss (gain)	982	632	(6,372)	(1,483)
Other expense (income), net	1,259	(1,013)	(2,362)	(962)
Income before income taxes	68,212	55,523	165,175	160,308
Income taxes	14,666	12,715	33,275	29,970
Net income	$ 53,546	$ 42,808	$ 131,900	$ 130,338
Income per share:
Basic (in dollars per share)	$ 2.13	$ 1.88	$ 5.31	$ 5.75
Diluted (in dollars per share)	$ 2.10	$ 1.87	$ 5.23	$ 5.69
Weighted-average shares and equivalent shares outstanding:
Basic (in shares)	25,109	22,713	24,817	22,678
Diluted (in shares)	25,471	22,953	25,212	22,906