Amount of cash proceeds that can be collected under transfer agreement

No definition available.

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Namespace Prefix:	k_
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Balance Type:	debit
Period Type:	instant

- Definition

Reflects the net positive or negative amount derived from subtracting from net proceeds of sale, the carrying amounts, net of allocated reserves, of accounts receivable transferred to a third party in a transaction that qualifies for sales treatment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=109247956&loc=d3e107425-111719

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of derecognized financial assets from transactions which comprise an initial transfer and an agreement entered into in contemplation of the initial transfer resulting in retention of substantially all of the exposure to the economic return throughout the term of the transaction, at the date of derecognition.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4D
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109247956&loc=SL51823488-111719

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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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Balance Type:	na
Period Type:	duration

- Details

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- Details

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- Details

Name:	us-gaap_QualitativeAndQuantitativeInformationTransferorsContinuingInvolvementTransferredFinancialAssetsByTransferOrTransfereeAxis=k_AccountsReceivableSoldAndOutstandingMember
Namespace Prefix:
Data Type:	na
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- Details

Name:	k_TransferOfAccountsReceivableProgramsAxis=k_KelloggForeignSubsidiariesOtherProgramMember
Namespace Prefix:
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Sale of Accounts Receivable - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 30, 2019	Mar. 31, 2018	Dec. 29, 2018
Monetization Program
Transfer of Financial Assets Accounted for as Sales [Line Items]
Gain (Loss) on Sale of Accounts Receivable	$ (8)	$ (7)
Monetization Program \| Maximum [Member]
Transfer of Financial Assets Accounted for as Sales [Line Items]
Transfers of Accounts Receivable Agreements	1,033
Monetization Program \| Sold And Outstanding
Transfer of Financial Assets Accounted for as Sales [Line Items]
Transfer of Financial Assets Accounted for as Sales, Amount Derecognized	944		$ 900
Kellogg Foreign Subsidiaries Other Program
Transfer of Financial Assets Accounted for as Sales [Line Items]
Transfers of Accounts Receivable Agreements	$ 29		$ 93