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Accrual for environmental loss contingencies, net of estimated insurance proceeds, total.

No definition available.

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The portion of the estimated aggregate undiscounted amount of the accrual for environmental loss contingencies that is expected to be paid, net of estimated insurance proceeds expected to be received, after the fifth year of the balance sheet date.

No definition available.

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No definition available.

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No definition available.

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No definition available.

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No definition available.

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No definition available.

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Accrual for Environmental Loss Contingencies, Net of Estimated Insurance Proceeds, Fiscal Year Maturity [Abstract]

No definition available.

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The estimated aggregate undiscounted amount of the estimated insurance proceeds accrual for environmental loss contingencies as of the balance sheet date.

No definition available.

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The portion of the estimated aggregate undiscounted amount of the insurance proceeds for environmental loss contingencies that is expected to be received after the fifth year of the balance sheet date.

No definition available.

Name:	unf_EstimatedInsuranceProceedsForEnvironmentalLossContingenciesUndiscountedDueAfterFifthYear
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The portion of the estimated aggregate undiscounted amount of the insurance proceeds for environmental loss contingencies that is expected to be received within five years of the balance sheet date.

No definition available.

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The portion of the estimated aggregate undiscounted amount of the insurance proceeds for environmental loss contingencies that is expected to be received within four years of the balance sheet date.

No definition available.

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The portion of the estimated aggregate undiscounted amount of the insurance proceeds for environmental loss contingencies that is expected to be received within two years of the balance sheet date.

No definition available.

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The portion of the estimated aggregate undiscounted amount of the insurance proceeds for environmental loss contingencies that is expected to be received within three years of the balance sheet date.

No definition available.

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The portion of the estimated aggregate undiscounted amount of the insurance proceeds for environmental loss contingencies that is expected to be received within one year of the balance sheet date.

No definition available.

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Estimated Insurance Proceeds for Environmental Loss Coontingencies, Fiscal Year Maturity [Abstract]

No definition available.

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Amount of imputed interest necessary to reduce (reconcile) the undiscounted amount of the accrual for environmental loss contingencies to the present value.

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- References

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Undiscounted amount of the accrual for environmental loss contingencies.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Undiscounted amount of accrual for environmental loss contingency to be paid after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Undiscounted amount of accrual for environmental loss contingency to be paid in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Undiscounted amount of accrual for environmental loss contingency to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Undiscounted amount of accrual for environmental loss contingency to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Undiscounted amount of accrual for environmental loss contingency to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Undiscounted amount of accrual for environmental loss contingency to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).