Debt Credit Facility (Details Textual)	3 Months Ended
Apr. 02, 2016 USD ($)	Jan. 02, 2016 USD ($)
Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Credit facility, interest rate description	Interest accrues on borrowings under the credit facility at either LIBOR plus a margin between 1.25% and 2.0% per annum or at the base rate plus a margin between 0.25% and 1.0% per annum. The interest rate applied to borrowings is determined by Cadence’s consolidated leverage ratio as specified by the credit facility agreement. Interest is payable quarterly.
Credit facility, maturity date	Sep. 19, 2019
Outstanding borrowings under Revolving Credit Facility	$ 50,000,000	$ 0
Credit facility, current borrowing capacity	250,000,000
Credit facility additional borrowing capacity available	150,000,000
Credit facility, maximum borrowing capacity	$ 400,000,000
Credit facility, covenant description	The credit facility contains customary negative covenants that, among other things, restrict Cadence’s ability to incur additional indebtedness, grant liens, make certain investments (including acquisitions), dispose of certain assets and make certain payments, including share repurchases and dividends. In addition, the credit facility contains financial covenants that require Cadence to maintain a leverage ratio not to exceed 2.75 to 1, and a minimum interest coverage ratio of 3 to 1.
Credit facility, covenant compliance	Cadence was in compliance with all financial covenants as of April 2, 2016 and January 2, 2016.
Maximum [Member] \| Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Credit facility, commitment fee percentage	0.35%
Minimum [Member] \| Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Credit facility, commitment fee percentage	0.20%
Credit Facility Interest LIBOR and spread [Member] \| Maximum [Member] \| Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Credit facility, interest rate spread	2.00%
Credit Facility Interest LIBOR and spread [Member] \| Minimum [Member] \| Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Credit facility, interest rate spread	1.25%
Credit facility interest base rate and spread [Member] \| Maximum [Member] \| Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Credit facility, interest rate spread	1.00%
Credit facility interest base rate and spread [Member] \| Minimum [Member] \| Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Credit facility, interest rate spread	0.25%
Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Covenant, Pro Forma Leverage Ratio	2.75
Debt Instrument, Covenant, Debt to EBITDA Ratio	3

Debt Instrument, Covenant, Debt to EBITDA Ratio

No definition available.

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- Definition

Debt Instrument, Covenant, Pro Forma Leverage Ratio

+ References

No definition available.

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- Definition

Line Of Credit Facility, Additional Borrowing Capacity Available

+ References

No definition available.

+ Details

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

Identification of whether the entity has been in compliance with any credit facility debt covenants during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 19, 22
-Article 5

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- Definition

Description of the conditions for borrowing under the credit facility including the nature of any restrictions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

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- Definition

Date the credit facility terminates, in CCYY-MM-DD format.

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- Definition

Description of the interest rate for the amounts borrowed under the credit facility, including the terms and the method for determining the interest rate (for example, fixed or variable, LIBOR plus a percentage, increasing rate, timing of interest rate resets, remarketing provisions).

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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- Definition

The carrying value as of the balance sheet date of the current portion of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Line-of-Credit Arrangement
-URI http://asc.fasb.org/extlink&oid=6517033

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.20)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 19, 20
-Article 5

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