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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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Balance Type:	credit
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
Namespace Prefix:	unf_
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Total costs accrued as of the balance sheet date for environmental loss contingencies.

Reference 1: http://www.xbrl.org/2003/role/recommendedDisclosureRef
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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.

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Amount of cash outflow to settle environmental loss contingencies.

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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.

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

Indicates line item in statement of financial position that includes accrual for environmental loss contingency.

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-Topic 410
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