XML 107 R53.htm IDEA: XBRL DOCUMENT
v3.19.3.a.u2

Summary of Significant Accounting Policies - Other (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 28, 2019 | Dec. 28, 2019 | Dec. 29, 2018 | Dec. 30, 2017
Accounting Policies [Abstract] |  |  |  |
Reserve for inventory |  | inventory in excess of 12-month demand |  |
Percentage of Revenue Mix Recognizable Over Time | 85.00% |  |  |
Advertising Expense |  | $ 8.4 | $ 7.6 | $ 7.4
Percentage of likelihood of tax benefit being realized upon effective settlement of audit |  | 50.00% |  |

X
- Definition Percentage of likelihood of tax benefit being realized upon effective settlement of audit. + References No definition available. + Details
Name: | cdns_PercentageOfLikelihoodOfTaxBenefitBeingRealizedUponEffectiveSettlementOfAudit
Namespace Prefix: | cdns_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of Revenue Mix Recognizable Over Time + References No definition available. + Details
Name: | cdns_PercentageofRevenueMixRecognizableOverTime
Namespace Prefix: | cdns_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Reserve for inventory. + References No definition available. + Details
Name: | cdns_ReserveForInventory
Namespace Prefix: | cdns_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_AccountingPoliciesAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 720 -SubTopic 35 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6420018&loc=d3e36677-107848 + Details
Name: | us-gaap_AdvertisingExpense
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration