Goodwill, Service Contracts and Other Assets - Changes in Carrying Amount of Goodwill (Details) $ in Thousands	9 Months Ended
Feb. 28, 2017 USD ($)
Goodwill [Roll Forward]
Beginning balance	$ 1,291,593
Goodwill acquired	12,044
Foreign currency translation	(599)
Ending balance	1,303,038
Uniform Rental and Facility Services
Goodwill [Roll Forward]
Beginning balance	953,216
Goodwill acquired	5,704
Foreign currency translation	(278)
Ending balance	958,642
First Aid and Safety Services
Goodwill [Roll Forward]
Beginning balance	241,448
Goodwill acquired	1,848
Foreign currency translation	(316)
Ending balance	242,980
All Other
Goodwill [Roll Forward]
Beginning balance	96,929
Goodwill acquired	4,492
Foreign currency translation	(5)
Ending balance	$ 101,416

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=64834752&loc=SL49117168-202975

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- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

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- Definition

Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

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