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BENEFIT PLANS - Additional Information (Details) $ in Millions	3 Months Ended	12 Months Ended
	Feb. 01, 2020 USD ($)	Jul. 31, 2021 USD ($)	Aug. 01, 2020 USD ($)
Retirement Benefits [Abstract]
Percentage of union employees that participate in multiemployer defined benefit pension plans under collective bargaining agreements		62.00%
Defined Benefit Plan Disclosure [Line Items]
Settlement charge (gain)		$ (12)	$ 9
Supervalu Retirement Plan
Defined Benefit Plan Disclosure [Line Items]
Settlement charge (gain)	$ (2)
Supervalu Retirement Plan | Measurement Input, Discount Rate
Defined Benefit Plan Disclosure [Line Items]
Measurement input (as a percent)	0.031

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Defined Benefit Plan, Measurement Input

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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.

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- Definition

Percentage of entity's employees covered by collective-bargaining arrangement (CBA) to all participants in multiemployer pension plan determined to be individually significant.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 80
-Section 50
-Paragraph 5
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450657-114947

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Amount, after tax, of increase (decrease) to other comprehensive income from settlement and curtailment gain (loss) of defined benefit plan.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
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-Section 45
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-Topic 220
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-Section 45
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