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Long term inflation rate assumption used in models to determine expected long-term rates of return on consolidated pension and other postretirement benefit plan assets.

No definition available.

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Active management premium percentage used in models to determine expected long-term rates of return on consolidated pension and other postretirement benefit plan assets.

No definition available.

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Percentage Of Pension And Other Postretirement Benefit Plan Assets

No definition available.

Name:	k_PercentageOfPensionAndOtherPostretirementBenefitPlanAssets
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Amount of gain (loss) from change in actuarial assumptions which (increases) decreases benefit obligation of defined benefit plan. Assumptions include, but are not limited to, interest, mortality, employee turnover, salary, and temporary deviation from substantive plan.

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Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan.

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Weighted average rate increase of compensation, used to determine benefit obligation of defined benefit plan. Plan includes, but is not limited to, pay-related defined benefit plan.

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Weighted average rate for present value of future retirement benefits cash flows, used to determine net periodic benefit cost of defined benefit plan.

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Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(3)
-URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e2919-114920

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Weighted average rate of compensation increase used to determine net periodic benefit cost of defined benefit plan. Plan includes, but is not limited to, pay-related defined benefit plan.

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Data Type:	dtr-types:percentItemType
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Period Type:	duration

Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

Name:	us-gaap_DefinedBenefitPlanBenefitObligation
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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

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_DefinedBenefitPlanDisclosureLineItems
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Data Type:	xbrli:stringItemType
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Description of basis used to determine overall expected long-term rate-of-return assumption for plan asset of defined benefit plan. Includes, but is not limited to, approach used, and extent approach was based on historical return and adjustment made to reflect expectation of future return.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(iii)
-URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
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Name:	us-gaap_RetirementPlanTypeAxis=us-gaap_PensionPlansDefinedBenefitMember
Namespace Prefix:
Data Type:	na
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Name:	srt_RangeAxis=srt_MinimumMember
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Name:	srt_RangeAxis=srt_MaximumMember
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Name:	us-gaap_RetirementPlanSponsorLocationAxis=k_GlobalPlansMember
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Data Type:	na
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Name:	us-gaap_RetirementPlanSponsorLocationAxis=country_US
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