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Goodwill, Service Contracts and Other Assets - Changes in Carrying Amount of Goodwill (Details) - USD ($) $ in Thousands | 12 Months Ended
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May 31, 2018 | May 31, 2017
Goodwill [Roll Forward] |  |
Balance at the beginning of the period | $ 2,782,335 | $ 1,276,076
Goodwill acquired | 61,461 | 1,507,554
Foreign currency translation | 3,092 | (1,295)
Balance at the end of the period | 2,846,888 | 2,782,335
G & K Services |  |
Goodwill [Roll Forward] |  |
Preliminary purchase price allocation adjustment | 52,700 |
Operating Segments | Uniform Rental and Facility Services |  |
Goodwill [Roll Forward] |  |
Balance at the beginning of the period | 2,448,070 | 949,730
Goodwill acquired | 55,152 | 1,499,008
Foreign currency translation | 2,254 | (668)
Balance at the end of the period | 2,505,476 | 2,448,070
Operating Segments | First Aid and Safety Services |  |
Goodwill [Roll Forward] |  |
Balance at the beginning of the period | 243,112 | 241,448
Goodwill acquired | 370 | 2,265
Foreign currency translation | 797 | (601)
Balance at the end of the period | 244,279 | 243,112
Operating Segments | All Other |  |
Goodwill [Roll Forward] |  |
Balance at the beginning of the period | 91,153 | 84,898
Goodwill acquired | 5,939 | 6,281
Foreign currency translation | 41 | (26)
Balance at the end of the period | $ 97,133 | $ 91,153

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- Definition 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. + References 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 + Details
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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 + Details
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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 + Details
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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 No definition available. + Details
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