XML 65 R57.htm IDEA: XBRL DOCUMENT
v3.25.2

Commitments and Contingencies - Changes to Environmental Liabilities (Details) - USD ($) $ in Thousands | 9 Months Ended
--- | ---
May 31, 2025 | May 25, 2024
Accrual for Environmental Loss Contingencies [Roll Forward] |  |
Beginning balance | $ 31,255 |
Costs incurred for which reserves have been provided | (1,899) |
Insurance proceeds | 190 |
Interest accretion | 960 | $ 948
Changes in discount rates | (1,409) |
Revisions in estimates | 1,711 |
Ending balance | $ 30,808 |
Environmental Loss Contingency, Statement of Financial Position [Extensible Enumeration] | Accounts Payable and Accrued Liabilities, Noncurrent |

X
- Definition Amount of accretion expense recognized in the income statement during the period that is associated with environmental contingencies. Accretion expense measures and incorporates changes due to the passage of time into the carrying amount of the liability. + References No definition available. + Details
Name: | unf_AccretionOnEnvironmentalContingencies
Namespace Prefix: | unf_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of discount applied to the future cost of environmental remediation to present value. + References No definition available. + Details
Name: | unf_EnvironmentalLiabilitiesChangesInDiscountRates
Namespace Prefix: | unf_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Recorded amount of the individual components comprising the asset for insurance recoveries related to environmental remediation obligations. + References No definition available. + Details
Name: | unf_RecordedInsuranceEnvironmentalRecoveriesAmount
Namespace Prefix: | unf_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Total costs accrued as of the balance sheet date for environmental loss contingencies. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 450 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147483076/450-20-50-1 Reference 2: http://www.xbrl.org/2003/role/recommendedDisclosureRef -Topic 410 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 10 -Subparagraph (d)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481931/410-30-50-10 Reference 3: http://www.xbrl.org/2003/role/recommendedDisclosureRef -Topic 410 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 10 -Subparagraph (d)(3) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481931/410-30-50-10 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Topic 410 -SubTopic 30 -Name Accounting Standards Codification -Section 55 -Paragraph 16 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481899/410-30-55-16 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 450 -SubTopic 20 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 5.Y.Q1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480102/450-20-S99-1 Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 410 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 7 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481931/410-30-50-7 + Details
Name: | us-gaap_AccrualForEnvironmentalLossContingencies
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of expense (reversal of expense) which increases (decreases) the accrual for environmental loss contingencies from revisions in estimates to existing obligations. Excludes changes related to business acquisitions, divestitures, or currency movement. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 450 -SubTopic 20 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 5.Y.Q1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480102/450-20-S99-1 + Details
Name: | us-gaap_AccrualForEnvironmentalLossContingenciesIncreaseDecreaseForRevisionInEstimates
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of cash outflow to settle environmental loss contingencies. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 450 -SubTopic 20 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 5.Y.Q1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480102/450-20-S99-1 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 230 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 17 -Subparagraph (f) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482740/230-10-45-17 + Details
Name: | us-gaap_AccrualForEnvironmentalLossContingenciesPayments1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
Name: | us-gaap_AccrualForEnvironmentalLossContingenciesRollForward
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Indicates line item in statement of financial position that includes accrual for environmental loss contingency. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 450 -SubTopic 20 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 5.Y.Q4) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480102/450-20-S99-1 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 410 -SubTopic 30 -Name Accounting Standards Codification -Section 55 -Paragraph 16 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481899/410-30-55-16 + Details
Name: | us-gaap_EnvironmentalLossContingencyStatementOfFinancialPositionExtensibleEnumeration
Namespace Prefix: | us-gaap_
Data Type: | enum2:enumerationSetItemType
Balance Type: | na
Period Type: | instant