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ACCOUNTING POLICIES - Policies (Details) | 3 Months Ended | 6 Months Ended
--- | --- | ---
Aug. 18, 2018 | Aug. 12, 2017 | Aug. 18, 2018 | Aug. 12, 2017
Fiscal Year |  |  |  |
Length of fiscal period | 84 days | 84 days | 196 days | 196 days

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- References No definition available. + Details
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Namespace Prefix: | kr_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

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- Definition Duration of a fiscal period, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Includes, but not limited to, weeks in a year or quarter. + References No definition available. + Details
Name: | us-gaap_FiscalPeriodDuration
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration