Revenue (Details)	3 Months Ended			9 Months Ended
	Oct. 02, 2021	Sep. 26, 2020		Oct. 02, 2021		Sep. 26, 2020
Revenue from External Customer [Line Items]
Percentage of product and maintenance revenue by product group	100.00%	100.00%		100.00%		100.00%
Custom Integrated Circuit (“IC”) Design and Simulation
Revenue from External Customer [Line Items]
Percentage of product and maintenance revenue by product group	23.00%	24.00%		23.00%		25.00%
Digital IC Design and Signoff
Revenue from External Customer [Line Items]
Percentage of product and maintenance revenue by product group	29.00%	27.00%		28.00%		28.00%
Functional Verification, including Emulation and Prototyping Hardware*
Revenue from External Customer [Line Items]
Percentage of product and maintenance revenue by product group	23.00%	23.00%	[1]	25.00%	[1]	23.00%	[1]
Intellectual Property (“IP”)
Revenue from External Customer [Line Items]
Percentage of product and maintenance revenue by product group	14.00%	15.00%		13.00%		14.00%
System Design and Analysis
Revenue from External Customer [Line Items]
Percentage of product and maintenance revenue by product group	11.00%	11.00%		11.00%		10.00%

[1] Includes immaterial amount of revenue accounted for under leasing arrangements.