Acquisitions and Acquisition-Related Contingent Consideration (Details Textual 1) (USD $) In Millions, unless otherwise specified	9 Months Ended
Sep. 27, 2014
Business Acquisition, Contingent Consideration [Line Items]
Maximum amount obligated to pay by Cadence	$ 10.0
Period over which Consideration May be Paid	19 months
Portion of amount of contingent consideration potential expense in future periods	$ 8.3

Business combination asset purchase contingent consideration maximum potential expense in future period.

No definition available.

Name:	cdns_BusinessCombinationAssetPurchaseContingentConsiderationMaximumPotentialExpenseInFuturePeriod
Namespace Prefix:	cdns_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration