Document and Entity Information (USD $)	12 Months Ended
	Jan. 03, 2015	Feb. 07, 2015	Jun. 28, 2014
Document and Entity Information [Abstract]
Entity Registrant Name	CADENCE DESIGN SYSTEMS INC
Entity Central Index Key	0000813672
Document Type	10-K
Document Period End Date	Jan. 03, 2015
Amendment Flag	false
Document Fiscal Year Focus	2014
Document Fiscal Period Focus	FY
Current Fiscal Year End Date	--01-03
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Public Float			$ 5,029,294,000
Entity Common Stock, Shares Outstanding		292,324,000