Name:	unf_AccretionOnEnvironmentalContingencies
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Amount of discount applied to the future cost of environmental remediation to present value.

No definition available.

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Period Type:	duration

Recorded amount of the individual components comprising the asset for insurance recoveries related to environmental remediation obligations.

No definition available.

Name:	unf_RecordedInsuranceEnvironmentalRecoveriesAmount
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Period Type:	duration

Total costs accrued as of the balance sheet date for environmental loss contingencies.

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Amount of cash outflow to settle environmental loss contingencies.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section S99
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.