Name:	k_PayablesFinancedByParticipatingSuppliers
Namespace Prefix:	k_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Amount of payables financed by suppliers that had been placed on the accounts payable tracking system which facilitates participating suppliers' ability to finance payment obligations from the company with designated third party financial institutions.

No definition available.

Name:	k_PayablesPlacedOnTrackingSystem
Namespace Prefix:	k_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Tax Cuts and Jobs Act reclassification from AOCI to retained earnings tax effect.

No definition available.

Name:	k_TaxCutsandJobsActReclassificationfromAOCIToRetainedEarningsTaxEffect
Namespace Prefix:	k_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

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.

No definition available.

Name:	us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Present value of lessee's discounted obligation for lease payments from operating lease.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977

Name:	us-gaap_OperatingLeaseLiability
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Amount of lessee's right to use underlying asset under operating lease.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977