Guarantor Obligations, Guarantees Term

No definition available.

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- Definition

Guarantor Obligations, Maximum Exposure, Discounted

+ References

No definition available.

+ Details

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Namespace Prefix:	unfi_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Loss Contingency, Cases Consolidated, Number

+ References

No definition available.

+ Details

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- Definition

Loss Contingency, Share of Potential Award, Value

+ References

No definition available.

+ Details

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Namespace Prefix:	unfi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI https://asc.fasb.org/extlink&oid=124440162&loc=d3e12069-110248

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

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

- Definition

Amount of loss contingency liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=121557415&loc=d3e14326-108349

Reference 2: http://www.xbrl.org/2003/role/recommendedDisclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 10
-URI https://asc.fasb.org/extlink&oid=121557415&loc=d3e14615-108349

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The value (monetary amount) of the award the plaintiff seeks in the legal matter.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=121557415&loc=d3e14435-108349

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=121557415&loc=d3e14326-108349

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=121557415&loc=d3e14557-108349

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The total number of new claims filed pertaining to a loss contingency during the period.

+ References

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of pending claims pertaining to a loss contingency.

+ References

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Minimum amount of purchase arrangement in which the entity has agreed to expend funds to procure goods or services from a supplier.

+ References

No definition available.

+ Details

Name:	us-gaap_PurchaseObligation
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

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Name:	us-gaap_LossContingenciesByNatureOfContingencyAxis=us-gaap_IndemnificationGuaranteeMember
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COMMITMENTS, CONTINGENCIES AND OFF-BALANCE SHEET ARRANGEMENTS (Details) $ in Millions		12 Months Ended
	Jan. 21, 2021 case	Jul. 30, 2022 USD ($) lawsuit case
Loss Contingencies [Line Items]
Purchase obligation		$ 388
Complaint From Various Health Plans
Loss Contingencies [Line Items]
Number of causes of action \| case	6
Schutte and Yarberry v. Supervalu, New Albertson's, Inc., et al
Loss Contingencies [Line Items]
Alleged damages (in excess of)		100
Share of potential award		$ 24
Advantage Logistics \| National Opioid Epidemic
Loss Contingencies [Line Items]
Number of suits pending \| lawsuit		43
Number of cases consolidated \| case		1,800
Guarantee Obligations
Loss Contingencies [Line Items]
Estimated loss		$ 1
Indemnification Agreement
Loss Contingencies [Line Items]
Estimated loss		0
Payment Guarantee
Loss Contingencies [Line Items]
Guarantor obligations, maximum exposure, undiscounted		22
Guarantor obligations, maximum exposure, discounted		$ 19
Payment Guarantee \| Minimum
Loss Contingencies [Line Items]
Guarantor obligations, guarantees term		1 year
Payment Guarantee \| Weighted Average
Loss Contingencies [Line Items]
Guarantor obligations, guarantees term		4 years
Payment Guarantee \| Maximum
Loss Contingencies [Line Items]
Guarantor obligations, guarantees term		8 years