Condensed Consolidated Statements of Net Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 28, 2020	Mar. 30, 2019
Income Statement [Abstract]
Net sales	$ 346,096	$ 405,500
Cost of sales	222,384	250,272
Gross profit	123,712	155,228
Selling, general, and administrative expenses	54,386	62,955
Research and development expenses	14,595	21,409
Amortization of intangibles	9,981	10,191
Total operating expenses	78,962	94,555
Operating income	44,750	60,673
Interest expense	5,418	5,686
Foreign exchange loss	2,584	4,243
Other expense, net	1,249	4,305
Income before income taxes	35,499	46,439
Income taxes	10,855	9,450
Net income	$ 24,644	$ 36,989
Income per share:
Basic (in dollars per share)	$ 1.01	$ 1.50
Diluted (in dollars per share)	$ 1.00	$ 1.48
Weighted-average shares and equivalent shares outstanding:
Basic (in shares)	24,393	24,717
Diluted (in shares)	24,578	25,009