Acquisitions (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Aug. 27, 2011	Aug. 28, 2010	Aug. 29, 2009
Finite-Lived Intangible Assets [Line Items]
Total intangible assets and goodwill acquired	$ 26,367	$ 17,113
Series of Individually Immaterial Business Acquisitions [Member]
Business Acquisition [Line Items]
Number of businesses acquired	9	9	12
Tangible assets acquired	6,189	3,795	467
Intangible assets and goodwill acquired	26,367	17,113	4,263
Acquisition of businesses	32,556	20,908	4,730
US and Canadian Rental and Cleaning Segment [Member]
Goodwill [Line Items]
Balance at end of period	16,014	10,584
Customer Contracts [Member]
Goodwill [Line Items]
Balance at end of period	9,588	6,008
Finite-Lived Intangible Assets [Line Items]
Weighted Average Life in Years	14.4	15.0
Other Intangible Assets [Member]
Goodwill [Line Items]
Balance at end of period	$ 765	$ 521
Finite-Lived Intangible Assets [Line Items]
Weighted Average Life in Years	5.1	5.0

The amount of acquisition cost of a business combination allocated to intangible assets and goodwill.

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- Definition

Carrying amount as of the balance sheet date, for intangible assets and goodwill acquired in a business combination.

+ Details

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- Definition

The aggregate amount assigned to a major class of finite-lived intangible assets acquired either individually or as part of a group of assets (in either an asset acquisition or business combination). A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 142

-Paragraph 44

-Subparagraph a(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6905858&loc=d3e16265-109275

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- Definition

The total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 51

-Subparagraph d

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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- 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.

+ Details

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- Definition

The amount of acquisition cost of a business combination allocated to tangible assets.

+ Details

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- Definition

The average useful life of a major finite-lived intangible asset class. A major class is composed of intangible assets that can be grouped together because they are similar either by their nature or by their use in the operations of a company.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=6905858&loc=d3e16265-109275

+ Details

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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.

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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.

+ Details

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- Definition

The number of businesses acquired by the entity during the period.

+ Details

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