XML 123 R103.htm IDEA: XBRL DOCUMENT v3.21.2

BENEFIT PLANS - Significant Multiemployer Plans (Details) $ in Millions	12 Months Ended
	Jul. 31, 2021 USD ($) Plan	Aug. 01, 2020 USD ($)	Aug. 03, 2019 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Contributions	$ 48	$ 52	$ 41
PPA surcharges (as a percent)	5.00%	10.00%
Minneapolis Food Distributing Industry Pension Plan
Defined Benefit Plan Disclosure [Line Items]
FIP/RP Status Pending/Implemented	No
Contributions	$ 12	$ 11	8
Surcharges Imposed	No
Minneapolis Retail Meat Cutters and Food Handlers Pension Fund
Defined Benefit Plan Disclosure [Line Items]
FIP/RP Status Pending/Implemented	Implemented
Contributions	$ 10	9	7
Surcharges Imposed	No
Minneapolis Retail Meat Cutters and Food Handlers Variable Annuity Pension Fund
Defined Benefit Plan Disclosure [Line Items]
FIP/RP Status Pending/Implemented	NA
Contributions	$ 4	3	1
Surcharges Imposed	NA
Central States, Southeast and Southwest Areas Pension Fund
Defined Benefit Plan Disclosure [Line Items]
FIP/RP Status Pending/Implemented	Implemented
Contributions	$ 6	6	5
Surcharges Imposed	No
UFCW Unions and Participating Employer Pension Fund
Defined Benefit Plan Disclosure [Line Items]
FIP/RP Status Pending/Implemented	Implemented
Contributions	$ 3	7	4
Surcharges Imposed	No
Western Conference of Teamsters Pension Plan Trust
Defined Benefit Plan Disclosure [Line Items]
FIP/RP Status Pending/Implemented	No
Contributions	$ 10	13	12
Surcharges Imposed	No
UFCW Unions and Employers Pension Plan
Defined Benefit Plan Disclosure [Line Items]
FIP/RP Status Pending/Implemented	Implemented
Contributions	$ 1	1	1
Surcharges Imposed	No
All Other Multiemployer Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Contributions	$ 2	$ 2	$ 3
Number of plans included in All Other Multiemployer Pension Plans | Plan	9
Number of plans without future contributions | Plan	2

X

- Definition

Multiemployer Plan, Number of Plans

+ References

No definition available.

+ Details

Name:	unfi_MultiemployerPlanNumberofPlans
Namespace Prefix:	unfi_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Multiemployer Plan, PPA Surcharges on Eligible Contributions, Percent

+ References

No definition available.

+ Details

Name:	unfi_MultiemployerPlanPPASurchargesonEligibleContributionsPercent
Namespace Prefix:	unfi_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Multiemployer Plan, Pension, Number Of Plans Without Future Contributions

+ References

No definition available.

+ Details

Name:	unfi_MultiemployerPlanPensionNumberOfPlansWithoutFutureContributions
Namespace Prefix:	unfi_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

X

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

X

- Definition

Amount of cost for employer contribution to multiemployer plan. Multiemployer plan includes, but is not limited to, pension plan determined to be individually significant and insignificant and other postretirement benefit plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 80
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=35742348&loc=SL14450788-114948

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 80
-Section 35
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=29639808&loc=d3e29008-114946

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 80
-Section 50
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450702-114947

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 80
-Section 50
-Paragraph 9
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450691-114947

+ Details

Name:	us-gaap_MultiemployerPlanEmployerContributionCost
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Indicates whether funding improvement plan or rehabilitation plan was implemented or pending for multiemployer pension plan, determined to be individually significant. Acceptable values are "No", "Pending", "Implemented", "Other", and "NA".

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 80
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=35742348&loc=SL14450788-114948

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 80
-Section 50
-Paragraph 5
-Subparagraph (f)(1)
-URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450657-114947

+ Details

Name:	us-gaap_MultiemployerPlanPensionSignificantFundingImprovementOrRehabilitationPlanImplementationStatusFixedList
Namespace Prefix:	us-gaap_
Data Type:	us-types:fundingImprovementAndRehabilitationPlanItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Indicates whether employer paid surcharge to multiemployer pension plan determined to be individually significant. Acceptable values are "No", "Yes" and "NA".

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 80
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=35742348&loc=SL14450788-114948

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 80
-Section 50
-Paragraph 5
-Subparagraph (f)(2)
-URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450657-114947

+ Details

Name:	us-gaap_MultiemployerPlanPensionSignificantSurchargeFixedList
Namespace Prefix:	us-gaap_
Data Type:	us-types:surchargeItemType
Balance Type:	na
Period Type:	duration

X

- Details

Name:	us-gaap_RetirementPlanNameAxis=unfi_MinneapolisFoodDistributingIndustryPensionPlanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_RetirementPlanNameAxis=unfi_MinneapolisRetailMeatCuttersAndFoodHandlersPensionFundMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_RetirementPlanNameAxis=unfi_MinneapolisRetailMeatCuttersAndFoodHandlersVariableAnnuityPensionFundMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_RetirementPlanNameAxis=unfi_CentralStatesSoutheastandSouthwestAreasPensionFundMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_RetirementPlanNameAxis=unfi_UFCWUnionsAndParticipatingEmployersPensionFundMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_RetirementPlanNameAxis=unfi_WesternConferenceOfTeamstersPensionPlanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_RetirementPlanNameAxis=unfi_UfcwUnionsAndEmployersPensionPlanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_RetirementPlanNameAxis=unfi_AllOtherMultiemployerPensionPlansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: