Estimated Incentives

No definition available.

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- Definition

Related Party Transaction, Estimated Future Expense

+ References

No definition available.

+ Details

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- Definition

Remaining Incentive

+ References

No definition available.

+ Details

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- Definition

Describes an existing condition, situation, or set of circumstances involving uncertainty as of the balance sheet date (or prior to issuance of the financial statements) as to a probable or reasonably possible gain to the entity that will ultimately be realized when one or more future events occur.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 30
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6397426&loc=d3e17499-108355

+ Details

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- Definition

Amount of transactions with related party during the financial reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39603-107864

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-Subparagraph (c)
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- Definition

A description of the related party transaction, including transactions to which no amounts or nominal amounts were ascribed and such other information deemed necessary to an understanding of the effects of the transactions on the financial statements. Examples of common related party transactions are, sales, purchases and transfers of realty and personal property, services received or furnished, loans and leases to and from top management and affiliates.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
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-Publisher SEC
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-Paragraph b
-Article 3A

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-Name Regulation S-X (SX)
-Number 210
-Section 08
-Paragraph k
-Subparagraph 2
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+ Details

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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.

+ Details

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- Details

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- Details

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- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=cern_TrailsMember
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Period Type:

- Details

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- Details

Name:	cern_TypeofIncentiveAxis=cern_SalesTaxExemptionsMember
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- Details

Name:	cern_TypeofIncentiveAxis=cern_StateIncomeTaxCreditsMember
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- Details

Name:	cern_TypeofIncentiveAxis=cern_LandReceivedMember
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- Details

Name:	us-gaap_GainContingenciesByNatureAxis=cern_SuccessPaymentMember
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Related Party Transactions Related Parties (Details) - USD ($) $ in Millions	12 Months Ended
	Jan. 02, 2016	Dec. 28, 2013
Related Party Transaction [Line Items]
Estimated Incentives	$ 82
Kansas Unified Development and OnGoal [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Description of Transaction	The stadium complex was developed by Kansas Unified Development, LLC (the “Developer”), an entity controlled by Neal Patterson, Chairman of the Board of Directors and Chief Executive Officer of the Company, and Clifford Illig, Vice Chairman of the Board of Directors of the Company. Sporting Kansas City (“Sporting KC”) is the principal tenant of the stadium complex. OnGoal LLC (“OnGoal”), the owner of the Sporting KC professional soccer club, is also controlled by Messrs. Patterson and Illig
Grand Construction [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Description of Transaction	GRAND Construction, LLC ("Grand") is a limited liability company owned in part by an entity controlled by Messrs. Patterson and Illig. Grand has historically provided construction management and related services to the Company in connection with our office campuses
Related Party Transaction, Amounts of Transaction	$ 2
Related Party Transaction, Estimated Future Expense	3
Trails [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Description of Transaction		In December 2013, we purchased approximately 237 acres of land located in Kansas City, Missouri, from Trails Properties II, Inc. (“Trails”)
Related Party Transaction, Amounts of Transaction		$ 43
Cash Grant [Member]
Related Party Transaction [Line Items]
Estimated Incentives	$ 48
Remaining Incentive	35
Sales Tax Exemptions [Member]
Related Party Transaction [Line Items]
Estimated Incentives	$ 11
State Income Tax Credits [Member]
Related Party Transaction [Line Items]
Estimated Incentives	19
Land Received [Member]
Related Party Transaction [Line Items]
Estimated Incentives	$ 4
Success Payment [Member]
Related Party Transaction [Line Items]
Gain Contingency, Description	Under a separate agreement, the Developer and OnGoal have agreed to be responsible for certain shortfall payments that may become due. If no payment from Developer or OnGoal becomes due at the end of the 10-year period, the Developer or OnGoal will pay us a success fee of $4 million
Cash Grant [Member]
Related Party Transaction [Line Items]
Gain Contingency, Description	Should aggregate state payroll tax withholdings (related to associates at our Continuous Campus) over a 10-year period commencing in January 2014 be less than $49 million (the $48 million of cash we received plus amounts representing debt service costs incurred by the State of Kansas), we would be required to repay the shortfall. The $49 million maximum repayment amount will be adjusted up or down during the 10-year period, based on any future change to Kansas payroll tax withholding rates