Segment Reporting (Details) - USD ($) $ in Thousands	12 Months Ended
Jan. 02, 2016	Jan. 03, 2015	Dec. 28, 2013
Entity Wide Disclosure on Geographic Areas Revenue from External Customers
Total revenue	$ 1,702,091	$ 1,580,932	$ 1,460,116
Americas:
Total Americas	808,379	719,965	671,654
UNITED STATES
Entity Wide Disclosure on Geographic Areas Revenue from External Customers
Geographic Areas, revenue from External Customers attributed to Individual Foreign Countries	782,419	696,608	648,714
Other Americas [Member]
Entity Wide Disclosure on Geographic Areas Revenue from External Customers
Geographic Areas, revenue from External Customers attributed to Individual Foreign Countries	25,960	23,357	22,940
Asia [Member]
Entity Wide Disclosure on Geographic Areas Revenue from External Customers
Geographic Areas, revenue from External Customers attributed to Individual Foreign Countries	413,588	360,280	289,065
Europe, Middle East and Africa [Member]
Entity Wide Disclosure on Geographic Areas Revenue from External Customers
Geographic Areas, revenue from External Customers attributed to Individual Foreign Countries	316,684	328,724	303,593
Japan [Member]
Entity Wide Disclosure on Geographic Areas Revenue from External Customers
Geographic Areas, revenue from External Customers attributed to Individual Foreign Countries	$ 163,440	$ 171,963	$ 195,804

Entity wide disclosure on geographic areas revenue from external customers attributed to country of domicile and other foreign countries.

No definition available.

+ Details

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Namespace Prefix:	cdns_
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Balance Type:	credit
Period Type:	duration

- Definition

Entity wide disclosure on geographic areas revenue from external customers attributed to entity's country of domicile and other foreign countries.

+ References

No definition available.

+ Details

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- References

No definition available.

+ Details

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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

+ Details

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- Definition

Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

+ References

+ Details

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- Details

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