Goodwill, Service Contracts and Other Assets (Changes in Carrying Amount of Service Contracts) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	May 31, 2014	May 31, 2013
Service contracts [Roll Forward]
Balance at the beginning of the period	$ 92,153	$ 76,822
Service contracts acquired	7,738	36,083
Shredding transaction	(23,990)
Service contracts amortization	(20,795)	(20,704)
Foreign currency translation	569	(48)
Balance at the end of the period	55,675	92,153
Rental Uniforms and Ancillary Products [Member]
Service contracts [Roll Forward]
Balance at the beginning of the period	23,135	29,156
Service contracts acquired	0	0
Shredding transaction	0
Service contracts amortization	(5,961)	(6,002)
Foreign currency translation	(3)	(19)
Balance at the end of the period	17,171	23,135
Uniform Direct Sales [Member]
Service contracts [Roll Forward]
Balance at the beginning of the period	0	0
Service contracts acquired	0	0
Shredding transaction	0
Service contracts amortization	0	0
Foreign currency translation	0	0
Balance at the end of the period	0	0
First Aid, Safety and Fire Protection [Member]
Service contracts [Roll Forward]
Balance at the beginning of the period	32,811	29,334
Service contracts acquired	3,149	11,413
Shredding transaction	0
Service contracts amortization	(7,926)	(7,936)
Foreign currency translation	0	0
Balance at the end of the period	28,034	32,811
Document Management [Member]
Service contracts [Roll Forward]
Balance at the beginning of the period	36,207	18,332
Service contracts acquired	4,589	24,670
Shredding transaction	(23,990)
Service contracts amortization	(6,908)	(6,766)
Foreign currency translation	572	(29)
Balance at the end of the period	$ 10,470	$ 36,207