Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 27, 2020	Sep. 29, 2019	Sep. 27, 2020	Sep. 29, 2019
Income Statement [Abstract]
Revenue	$ 251,073	$ 183,325	$ 587,405	$ 555,856
Cost of revenue	59,741	47,632	151,261	144,883
Gross margin	191,332	135,693	436,144	410,973
Research, development, and engineering expenses	30,240	28,115	96,583	86,436
Selling, general, and administrative expenses	64,206	64,486	193,497	199,542
Restructuring charges (Note 16)	251	0	15,049	0
Intangible asset impairment charges (Note 8)	0	0	19,571	0
Operating income	96,635	43,092	111,444	124,995
Foreign currency gain (loss)	2,357	(1,295)	(310)	(1,403)
Investment income	2,490	5,114	11,010	15,242
Other income (expense)	(173)	456	(153)	1,239
Income before income tax expense	101,309	47,367	121,991	140,073
Income tax expense	13,803	5,682	15,150	16,535
Net Income	$ 87,506	$ 41,685	$ 106,841	$ 123,538
Net income per weighted-average common and common-equivalent share:
Basic (usd per share)	$ 0.50	$ 0.24	$ 0.62	$ 0.72
Diluted (usd per share)	$ 0.49	$ 0.24	$ 0.61	$ 0.71
Weighted-average common and common-equivalent shares outstanding:
Basic (shares)	173,943	170,744	172,881	171,053
Diluted (shares)	177,138	174,449	176,038	175,164
Cash dividends per common share (usd per share)	$ 0.055	$ 0.050	$ 0.165	$ 0.150