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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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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of liabilities incurred by the acquirer as part of consideration transferred in a business combination.

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Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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Acquisitions and Divestitures - Narrative (Details) $ in Millions		12 Months Ended
	Aug. 01, 2015 USD ($)	May 31, 2016 transaction segment_business	May 31, 2015 segment_business
Business Acquisition [Line Items]
Number of transactions involved in sale of business \| transaction		3
Series of Business Acquisitions \| Uniform Rental and Facility Services
Business Acquisition [Line Items]
Number of businesses acquired \| segment_business		2	1
Series of Business Acquisitions \| First Aid and Safety Services
Business Acquisition [Line Items]
Number of businesses acquired \| segment_business		2	3
Series of Business Acquisitions \| All Other
Business Acquisition [Line Items]
Number of businesses acquired \| segment_business		6	8
ZEE
Business Acquisition [Line Items]
Fair value of consideration \| $	$ 134.0
Business acquisition, consideration \| $	120.6
Contingent consideration \| $	$ 13.4
Service Contracts \| ZEE
Business Acquisition [Line Items]
Service contracts and other assets useful lives (years)		10 years
Level 3 \| ZEE
Business Acquisition [Line Items]
Discount rate income approach (as a percent)		11.00%