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Segment Information - Information Related to Operating Segments (Details) - USD ($) $ in Thousands	3 Months Ended
	Aug. 31, 2018	Aug. 31, 2017	Jun. 01, 2018	May 31, 2018
Segment Reporting Information
Revenue	$ 1,697,975	$ 1,611,503
Income (loss) before income taxes	241,420	219,079
Total assets	7,287,204	6,851,606	$ 7,211,341	$ 6,958,214
Operating Segments \| Uniform Rental and Facility Services
Segment Reporting Information
Revenue	1,374,938	1,311,784
Income (loss) before income taxes	231,534	218,910
Total assets	6,298,849	5,844,718
Operating Segments \| First Aid and Safety Services
Segment Reporting Information
Revenue	153,417	140,582
Income (loss) before income taxes	21,983	19,411
Total assets	486,965	456,391
Operating Segments \| All Other
Segment Reporting Information
Revenue	169,620	159,137
Income (loss) before income taxes	11,711	10,778
Total assets	383,034	337,457
Corporate
Segment Reporting Information
Revenue	0	0
Income (loss) before income taxes	(23,808)	(30,020)
Total assets	$ 118,356	$ 213,040