Stock Compensation Plans and Stock Based Compensation (Details 9) - Employee stock purchase plans [Member] - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Shares of common stock issued under employee stock purchase plan
Cadence shares purchased under the ESPP	892	1,270	1,471
Cash received for the purchase of shares under the ESPP	$ 29,160	$ 26,709	$ 24,450
Weighted-average purchase price per share	$ 32.69	$ 21.04	$ 16.62

Cash received for the purchase of shares under the ESPP.

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- Definition

Shares of common stock issued under employee stock purchase plan.

+ References

No definition available.

+ Details

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- Definition

The weighted average of per share prices paid for shares purchased on the open market for issuance to employees under the plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5047-113901

+ Details

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- Definition

The number of shares purchased on the open market during the period for issuance to employees under the plan.

+ References

+ Details

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