EARNINGS PER COMMON SHARE (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	4 Months Ended
May 23, 2020	May 25, 2019
EARNINGS PER COMMON SHARE
Net earnings numerator (basic)	$ 1,197	$ 764
Net earnings numerator (diluted)	$ 1,197	$ 764
Average number of common shares used in basic calculation	780	798
Net earnings attributable to The Kroger Co. per basic common share	$ 1.53	$ 0.96
Dilutive effect of stock options (in shares)	8	7
Average number of common shares used in diluted calculation	788	805
Net earnings attributable to The Kroger Co. per diluted common share	$ 1.52	$ 0.95
Undistributed and distributed earnings to participating securities	$ 15	$ 8
Shares excluded from the earnings per share calculation due to anti-dilutive effect on earnings per share	11	16

The amount of undistributed and distributed earnings to participating securities for the period.

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities; of income (loss) available to common shareholders.

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