Amount of cash proceeds that can be collected under transfer agreement

No definition available.

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Namespace Prefix:	k_
Data Type:	xbrli:monetaryItemType
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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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=64830801&loc=d3e107425-111719

+ Details

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

- Definition

A device of credit enhancement where a part of the purchase price for the receivable/ payable is retained to serve as a cash collateral.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4332-108586

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4313-108586

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4D
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=64830801&loc=SL51823488-111719

+ Details

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

- Definition

Amount, before counterparty netting, of cash proceeds received in transfers 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4D
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=64830801&loc=SL51823488-111719

+ Details

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

- Details

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- Details

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- Details

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- Details

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Namespace Prefix:
Data Type:	na
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Period Type:

- Details

Name:	k_TransferOfAccountsReceivableProgramsAxis=k_KelloggFundingCompanyProgramMember
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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		9 Months Ended		12 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Sep. 30, 2017	Oct. 01, 2016	Dec. 31, 2016	Jul. 01, 2017	Jul. 31, 2016
Receivables Sales Agreement
Transfer of Financial Assets Accounted for as Sales [Line Items]
Gain (Loss) on Sale of Accounts Receivable	$ (3)	$ (1)	$ (8)	$ (3)
Receivables Sales Agreement \| Maximum [Member]
Transfer of Financial Assets Accounted for as Sales [Line Items]
Transfers of Accounts Receivable Agreements	800		800			$ 700
Receivables Sales Agreement \| Sold And Outstanding
Transfer of Financial Assets Accounted for as Sales [Line Items]
Transfer of Financial Assets Accounted for as Sales, Amount Derecognized	629		629		$ 562
Receivables Sales Agreement \| Sold Since Inception
Transfer of Financial Assets Accounted for as Sales [Line Items]
Transfer of Financial Assets Accounted for as Sales, Amount Derecognized	1,700	1,000	1,700	1,000
Kellogg Funding Company Program
Transfer of Financial Assets Accounted for as Sales [Line Items]
Gain (Loss) on Sale of Accounts Receivable	(1)		(4)
Cash Proceeds Received for Assets Derecognized	433		433		255
Deferred Purchase Price			47		37
Kellogg Funding Company Program \| Maximum [Member]
Transfer of Financial Assets Accounted for as Sales [Line Items]
Transfers of Accounts Receivable Agreements							$ 600
Kellogg Funding Company Program \| Sold And Outstanding
Transfer of Financial Assets Accounted for as Sales [Line Items]
Transfer of Financial Assets Accounted for as Sales, Amount Derecognized	480		480		292
Kellogg Funding Company Program \| Sold Since Inception
Transfer of Financial Assets Accounted for as Sales [Line Items]
Transfer of Financial Assets Accounted for as Sales, Amount Derecognized	2,000	341	2,000	341
Kellogg Foreign Subsidiaries Other Program
Transfer of Financial Assets Accounted for as Sales [Line Items]
Transfers of Accounts Receivable Agreements	45		45		$ 124
Transfer of Financial Assets Accounted for as Sales, Amount Derecognized	$ 145	$ 33	$ 145	$ 33