Goodwill, Service Contracts and Other Assets - Changes in Carrying Amount of Service Contracts (Details) - USD ($) $ in Thousands	12 Months Ended
	May. 31, 2015	May. 31, 2014
Service contracts [Roll Forward]
Balance at the beginning of the period	$ 55,675	$ 92,153
Service contracts acquired	10,121	7,738
Service contracts divested	(9,570)	(23,990)
Service contracts amortization	(13,221)	(20,795)
Foreign currency translation	(571)	569
Balance at the end of the period	42,434	55,675
Corporate
Service contracts [Roll Forward]
Balance at the beginning of the period	10,470	36,207
Service contracts acquired	265	4,589
Service contracts divested	(9,570)	(23,990)
Service contracts amortization	(597)	(6,908)
Foreign currency translation	(568)	572
Balance at the end of the period	0	10,470
Operating Segments | Rental Uniforms & Ancillary Products
Service contracts [Roll Forward]
Balance at the beginning of the period	17,171	23,135
Service contracts acquired	313	0
Service contracts divested	0	0
Service contracts amortization	(5,619)	(5,961)
Foreign currency translation	(3)	(3)
Balance at the end of the period	11,862	17,171
Operating Segments | Uniform Direct Sales
Service contracts [Roll Forward]
Balance at the beginning of the period	0	0
Service contracts acquired	0	0
Service contracts divested	0	0
Service contracts amortization	0	0
Foreign currency translation	0	0
Balance at the end of the period	0	0
Operating Segments | First Aid, Safety & Fire Protection
Service contracts [Roll Forward]
Balance at the beginning of the period	28,034	32,811
Service contracts acquired	9,543	3,149
Service contracts divested	0	0
Service contracts amortization	(7,005)	(7,926)
Foreign currency translation	0	0
Balance at the end of the period	$ 30,572	$ 28,034