Goodwill, Service Contracts and Other Assets - Changes in Carrying Amount of Goodwill by Operating Segment (Details) $ in Thousands	3 Months Ended
Aug. 31, 2018 USD ($)
Goodwill [Roll Forward]
Beginning balance	$ 2,846,888
Goodwill acquired	4,964
Foreign currency translation	(1,770)
Ending balance	2,850,082
Uniform Rental and Facility Services
Goodwill [Roll Forward]
Beginning balance	2,505,476
Goodwill acquired	0
Foreign currency translation	(1,631)
Ending balance	2,503,845
First Aid and Safety Services
Goodwill [Roll Forward]
Beginning balance	244,279
Goodwill acquired	0
Foreign currency translation	(129)
Ending balance	244,150
All Other
Goodwill [Roll Forward]
Beginning balance	97,133
Goodwill acquired	4,964
Foreign currency translation	(10)
Ending balance	$ 102,087

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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266

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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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267

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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.

+ References

No definition available.

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