Defined Benefit Plan, Measurement Input

No definition available.

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Namespace Prefix:	unfi_
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Period Type:	instant

- Definition

Multiemployer Plan, Pension, Withdrawal Obligation, Period

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Amount of payment, which decreases benefit obligation of defined benefit plan, for irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Transaction constituting settlement includes, but is not limited to, making lump-sum cash payment to participant in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contract. Excludes decreases to benefit obligation for remeasurement due to settlement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)(10)
-URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920

+ Details

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

- 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

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

- Definition

Amount of contributions received and expected to be received by defined benefit plan from employer in current fiscal year.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 6
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-URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e2709-114920

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-Publisher FASB
-Name Accounting Standards Codification
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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- 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
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+ Details

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

- Definition

Amount of the obligation recognized by withdrawing from a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers.

+ References

No definition available.

+ Details

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

- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
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-Section 50
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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of noncash expense (reversal of expense) for pension benefits. Excludes other postretirement benefits.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Balance Type:	debit
Period Type:	duration

- Details

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Period Type:

- Details

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- Details

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BENEFIT PLANS - Narrative (Details) $ in Thousands	3 Months Ended			9 Months Ended
BENEFIT PLANS - Narrative (Details) $ in Thousands	May 01, 2021 USD ($)	May 02, 2020 USD ($)	Feb. 01, 2020 USD ($)	May 01, 2021 USD ($)	May 02, 2020 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, expected future employer contributions, current fiscal year	$ 5,300			$ 5,300
Multiemployer pension plan, withdrawal liability			$ 10,600
Multiemployer pension plan, payment period			1 year
Remeasurement, effect on AOCI					$ (7,610)
SUPERVALU Retirement Plan
Defined Benefit Plan Disclosure [Line Items]
Lump sum settlement payments			$ 664,000
Non-cash pension settlement charge			10,300
Remeasurement, effect on AOCI			$ 1,500
SUPERVALU Retirement Plan \| Measurement Input, Discount Rate
Defined Benefit Plan Disclosure [Line Items]
Measurement input			0.031
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Multiemployer plan, contributions by employer	$ 12,200	$ 12,300		$ 35,900	$ 38,400