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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Number of additional shares authorized for issuance under share-based payment arrangement.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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Gross number of share options (or share units) granted during the period.

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Per share or per unit amount of equity securities issued.

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SHARE-BASED AWARDS (Details) $ / shares in Units, $ in Thousands		2 Months Ended	3 Months Ended	12 Months Ended
	Oct. 22, 2018 $ / shares shares	Sep. 26, 2019 USD ($)	Feb. 01, 2020 USD ($)	Aug. 01, 2020 USD ($) Plan installment $ / shares shares	Aug. 03, 2019 USD ($) $ / shares shares	Jul. 28, 2018 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation cost \| $				$ 47,200
Weighted-average period over which cost is recognized				1 year 10 months 24 days
Number of additional shares (up to, in shares)	5,000,000
Shares of common stock issued (in shares)				1,349,655	2,004,730
Average price (in dollars per share) \| $ / shares				$ 10.66	$ 12.00
Cash received \| $				$ 14,333	$ 23,857
Cash received subsequent to end of fiscal year \| $		$ 400
Fixed value of expensed replacement award liabilities (in dollars per share) \| $ / shares				$ 32.50
Minimum years of service to company				10 years
Allocated share-based compensation expense \| $			$ 6,600
Equity Incentive Plan 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized and available for grant (in shares)				2,865,125
Equity Incentive Plan 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period				3 years
Stock option awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity incentive plans \| Plan				4
Stock options granted (in shares)				0	0	0
Aggregate intrinsic value \| $				$ 100	$ 100	$ 700
Allocated share-based compensation expense \| $				$ (111)	$ 199	$ 342
Performance Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of performance share units granted (in shares)				977,860
Number of additional shares (up to, in shares)				977,860
Weighted-average grant-date fair value (in dollars per share) \| $ / shares				$ 8.07
Performance share units forfeited (in shares)				0
2019 Performance Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of performance share units granted (in shares)					339,282
Number of additional shares (up to, in shares)					339,282
Weighted-average grant-date fair value (in dollars per share) \| $ / shares					$ 22.56
2018 Performance Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of performance share units granted (in shares)						109,100
Weighted-average grant-date fair value (in dollars per share) \| $ / shares						$ 39.74
Performance Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance share units forfeited (in shares)				261,483	6,620
Number of shares earned (in shares)				71,539
SUPERVALU
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation cost \| $				$ 6,300
Number of performance share units granted (in shares)					4,301,233
Weighted-average grant-date fair value (in dollars per share) \| $ / shares					$ 32.50
Cash payment (in dollars per share) \| $ / shares	$ 32.50
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of installments for employees \| installment				3
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of installments for employees \| installment				4
Additional Paid-in Capital [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cash received \| $				$ 14,320	$ 23,837