Accounts Receivable and Allowances for Doubtful Accounts (Details Textual)	Mar. 31, 2012 Customer	Dec. 31, 2011 Customer
Accounts Receivable and Allowances for Doubtful Accounts (Textual) [Abstract]
Number of customers accounted for percentage of Cadence's total receivables, net	0	0
Percent of receivables and installment contract receivables attributable to single customer	10.00%	10.00%
Percentage of Company's total receivables, net attributable to the ten customers with largest balance	41.00%	45.00%

Percentage of company's receivables net and installment contract receivables net attributable to ten customers with largest balance.

No definition available.

Name:	cdns_PercentageOfCompanysReceivablesNetAndInstallmentContractReceivablesNetAttributableToTenCustomersWithLargestBalance
Namespace Prefix:	cdns_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant