Goodwill, Service Contracts and Other Assets - Service Contracts (Details) - USD ($) $ in Thousands	12 Months Ended
	May 31, 2019	May 31, 2018
Service contracts [Roll Forward]
Balance at the beginning of the period	$ 545,768	$ 586,988
Service contracts acquired	8,064	9,393
Service contracts amortization	(56,190)	(54,044)
Foreign currency translation	(3,047)	3,431
Balance at the end of the period	494,595	545,768
Uniform rental and facility services
Service contracts [Roll Forward]
Balance at the beginning of the period	492,067	529,923
Service contracts acquired	2,864	4,098
Service contracts amortization	(46,943)	(45,296)
Foreign currency translation	(2,972)	3,342
Balance at the end of the period	445,016	492,067
First Aid and Safety Services
Service contracts [Roll Forward]
Balance at the beginning of the period	27,294	30,062
Service contracts acquired	14	985
Service contracts amortization	(3,853)	(3,842)
Foreign currency translation	(75)	89
Balance at the end of the period	23,380	27,294
All Other
Service contracts [Roll Forward]
Balance at the beginning of the period	26,407	27,003
Service contracts acquired	5,186	4,310
Service contracts amortization	(5,394)	(4,906)
Foreign currency translation	0	0
Balance at the end of the period	$ 26,199	$ 26,407