Goodwill, Service Contracts and Other Assets - Changes in Carrying Amount of Service Contracts (Details) - USD ($) $ in Thousands	12 Months Ended
	May 31, 2017	May 31, 2016
Service contracts [Roll Forward]
Balance at the beginning of the period	$ 78,194	$ 35,650
Service contracts acquired	529,235	55,694
Service contracts amortization	(20,510)	(13,129)
Foreign currency translation	69	(21)
Balance at the end of the period	586,988	78,194
Operating Segments | Uniform Rental and Facility Services
Service contracts [Roll Forward]
Balance at the beginning of the period	19,912	5,078
Service contracts acquired	521,708	18,912
Service contracts amortization	(11,636)	(4,078)
Foreign currency translation	(61)	0
Balance at the end of the period	529,923	19,912
Operating Segments | First Aid and Safety Services
Service contracts [Roll Forward]
Balance at the beginning of the period	32,252	1,576
Service contracts acquired	1,632	34,052
Service contracts amortization	(3,952)	(3,355)
Foreign currency translation	130	(21)
Balance at the end of the period	30,062	32,252
Operating Segments | All Other
Service contracts [Roll Forward]
Balance at the beginning of the period	26,030	28,996
Service contracts acquired	5,895	2,730
Service contracts amortization	(4,922)	(5,696)
Foreign currency translation	0	0
Balance at the end of the period	$ 27,003	$ 26,030