Condensed Consolidated Statements of Net Income (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 29, 2019	Jun. 30, 2018	Jun. 29, 2019	Jun. 30, 2018
Income Statement [Abstract]
Net sales	$ 397,879	$ 459,183	$ 803,379	$ 876,996
Cost of sales	256,071	290,196	506,343	558,386
Gross profit	141,808	168,987	297,036	318,610
Selling, general, and administrative expenses	57,666	73,244	120,621	150,758
Research and development expenses	21,458	22,748	42,867	45,288
Amortization of intangibles	10,050	13,373	20,241	25,371
Total operating expenses	89,174	109,365	183,729	221,417
Operating income	52,634	59,622	113,307	97,193
Interest expense	5,589	5,782	11,275	11,205
Foreign exchange (gain) loss	(3,575)	3,200	668	(7,354)
Other (income) expense, net	(2,947)	(1,678)	1,358	(3,621)
Income before income taxes	53,567	52,318	100,006	96,963
Income taxes	9,775	9,992	19,225	18,609
Net income	$ 43,792	$ 42,326	$ 80,781	$ 78,354
Income per share:
Basic (in dollars per share)	$ 1.77	$ 1.69	$ 3.27	$ 3.18
Diluted (in dollars per share)	$ 1.75	$ 1.67	$ 3.23	$ 3.12
Weighted-average shares and equivalent shares outstanding:
Basic (in shares)	24,740	25,004	24,729	24,671
Diluted (in shares)	24,983	25,401	24,998	25,086