Goodwill, Service Contracts and Other Assets - Service Contracts (Details) - USD ($) $ in Thousands	12 Months Ended
	May 31, 2020	May 31, 2019
Service contracts [Roll Forward]
Balance at the end of the period	$ 760,607
Service contracts
Service contracts [Roll Forward]
Balance at the beginning of the period	494,595	$ 545,768
Service contracts acquired	14,671	8,064
Service contracts amortization	(56,321)	(56,190)
Foreign currency translation	(1,416)	(3,047)
Balance at the end of the period	451,529	494,595
Uniform rental and facility services | Service contracts
Service contracts [Roll Forward]
Balance at the beginning of the period	445,016	492,067
Service contracts acquired	11,058	2,864
Service contracts amortization	(47,070)	(46,943)
Foreign currency translation	(1,393)	(2,972)
Balance at the end of the period	407,611	445,016
First Aid and Safety Services | Service contracts
Service contracts [Roll Forward]
Balance at the beginning of the period	23,380	27,294
Service contracts acquired	325	14
Service contracts amortization	(3,877)	(3,853)
Foreign currency translation	(23)	(75)
Balance at the end of the period	19,805	23,380
All Other | Service contracts
Service contracts [Roll Forward]
Balance at the beginning of the period	26,199	26,407
Service contracts acquired	3,288	5,186
Service contracts amortization	(5,374)	(5,394)
Foreign currency translation	0	0
Balance at the end of the period	$ 24,113	$ 26,199