Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Aug. 31, 2021	Aug. 31, 2020	May 31, 2021
Segment Reporting Information
Revenue	$ 1,896,950	$ 1,746,575
Income (loss) before income taxes	372,303	325,220
Total assets	7,857,750	8,043,381	$ 8,236,823
Uniform rental and facility services
Segment Reporting Information
Revenue	1,508,176	1,394,411
First Aid and Safety Services
Segment Reporting Information
Revenue	199,116	204,481
Operating Segments | Uniform rental and facility services
Segment Reporting Information
Revenue	1,508,176	1,394,411
Income (loss) before income taxes	329,382	315,028
Total assets	6,770,296	6,628,127
Operating Segments | First Aid and Safety Services
Segment Reporting Information
Revenue	199,116	204,481
Income (loss) before income taxes	25,728	18,527
Total assets	636,829	620,169
Operating Segments | All Other
Segment Reporting Information
Revenue	189,658	147,683
Income (loss) before income taxes	38,991	16,151
Total assets	370,876	373,543
Corporate
Segment Reporting Information
Revenue	0	0
Income (loss) before income taxes	(21,798)	(24,486)
Total assets	$ 79,749	$ 421,542