Represents the aggregate amount of purchase price of ordinary shares under collaborative arrangements.

No definition available.

Name:	kr_CollaborativeArrangementsAggregatePurchasePriceOfOrdinaryShares
Namespace Prefix:	kr_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Represents the amount of exclusivity fee to be paid and letter of credit under collaborative arrangements.

+ References

No definition available.

+ Details

Name:	kr_CollaborativeArrangementsExclusivityFeeToBePaidAndLetterOfCredit
Namespace Prefix:	kr_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents the number of ordinary shares purchased under collaborative arrangements.

+ References

No definition available.

+ Details

Name:	kr_CollaborativeArrangementsNumberOfOrdinarySharesPurchased
Namespace Prefix:	kr_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the number of ordinary shares to be purchased under collaborative arrangements.

+ References

No definition available.

+ Details

Name:	kr_CollaborativeArrangementsNumberOfOrdinarySharesToBePurchased
Namespace Prefix:	kr_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=99377092&loc=SL75136599-209740

+ Details

Name:	us-gaap_EquitySecuritiesFvNi
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of realized gain from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=116654751&loc=SL75117546-209714

+ Details

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

- Definition

Amount of unrealized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=116654751&loc=SL75117546-209714

+ Details

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

- 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

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

- Details

Name:	srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=kr_OcadoInternationalHoldingsLimitedAndOcadoGroupPlcMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_BalanceSheetLocationAxis=us-gaap_OtherAssetsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_OtherCommitmentsAxis=kr_PartnershipFrameworkAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_OtherCommitmentsAxis=kr_ShareSubscriptionAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

MERGER AND PARTNERSHIP AGREEMENTS - PARTNERSHIP AGREEMENT (Details) - USD ($) shares in Millions, $ in Millions			3 Months Ended						4 Months Ended		12 Months Ended
	May 29, 2018	May 17, 2018	Feb. 01, 2020	Nov. 09, 2019	Aug. 17, 2019	Feb. 02, 2019	Nov. 10, 2018	Aug. 18, 2018	May 25, 2019	May 26, 2018	Feb. 01, 2020	Feb. 02, 2019
Agreement and commitments
Unrealized (loss) gain on equity securities			$ (9)	$ 106	$ (45)	$ 75	$ (100)	$ 216	$ 106	$ 36	$ 157	$ 228
Ocado
Agreement and commitments
Unrealized (loss) gain on equity securities											157	228
Realized gain on equity securities											0	0
Ocado \| Other Assets
Agreement and commitments
Fair value of equity securities			$ 776			$ 620					$ 776	$ 620
Partnership Framework Agreement \| Ocado
Agreement and commitments
Letter of credit		$ 180
Share Subscription Agreement \| Ocado
Agreement and commitments
Number of ordinary shares to be purchased		33.1
Aggregate purchase price		$ 243
Number of ordinary shares purchased	33.1							6.5		8.1