Condensed Consolidated Income Statements - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 03, 2021	Jun. 27, 2020	Jul. 03, 2021	Jun. 27, 2020
Revenues [Abstract]
Revenues	$ 728,285	$ 638,418	$ 1,464,313	$ 1,256,375
Costs and Expenses:
Marketing and sales	135,967	120,476	268,793	246,220
Research and development	285,227	250,821	556,219	492,489
General and administrative	40,333	35,641	80,285	69,233
Amortization of acquired intangibles	5,030	4,590	9,661	8,796
Restructuring and other credits	(469)	(275)	(746)	(1,342)
Total costs and expenses	542,847	486,468	1,074,938	965,074
Income from operations	185,438	151,950	389,375	291,301
Interest expense	(4,316)	(5,914)	(8,533)	(10,551)
Other income, net	2,143	4,630	4,844	96
Income before provision for income taxes	183,265	150,666	385,686	280,846
Provision for income taxes	27,365	19,378	42,617	25,570
Net income	$ 155,900	$ 131,288	$ 343,069	$ 255,276
Net income per share - basic (usd per share)	$ 0.57	$ 0.48	$ 1.25	$ 0.93
Net Income per share - diluted (usd per share)	$ 0.56	$ 0.47	$ 1.23	$ 0.91
Weighted average common shares outstanding - basic (in shares)	273,565	273,432	273,843	273,488
Weighted average common shares outstanding - diluted (in shares)	278,558	279,080	279,399	279,207
Product and maintenance [Member]
Revenues [Abstract]
Revenues	$ 687,884	$ 601,356	$ 1,386,938	$ 1,183,055
Costs and Expenses:
Cost of sales	55,842	55,669	120,748	111,115
Service [Member]
Revenues [Abstract]
Revenues	40,401	37,062	77,375	73,320
Costs and Expenses:
Cost of sales	$ 20,917	$ 19,546	$ 39,978	$ 38,563