Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Nov. 30, 2020	Nov. 30, 2019	Nov. 30, 2020	Nov. 30, 2019	May 31, 2020
Segment Reporting Information
Revenue	$ 1,757,048	$ 1,843,749	$ 3,503,622	$ 3,654,888
Income (loss) before income taxes	328,533	308,570	653,753	587,557
Total assets	8,454,753	7,887,337	8,454,753	7,887,337	$ 7,669,885
Operating Segments | Uniform Rental and Facility Services
Segment Reporting Information
Revenue	1,410,488	1,469,976	2,804,899	2,924,503
Income (loss) before income taxes	315,609	286,360	630,637	555,371
Total assets	6,732,076	6,699,166	6,732,076	6,699,166
Operating Segments | First Aid and Safety Services
Segment Reporting Information
Revenue	194,419	169,668	398,899	341,758
Income (loss) before income taxes	21,506	24,640	40,033	49,409
Total assets	657,665	537,740	657,665	537,740
Operating Segments | All Other
Segment Reporting Information
Revenue	152,141	204,105	299,824	388,627
Income (loss) before income taxes	15,757	23,464	31,908	35,830
Total assets	361,837	423,896	361,837	423,896
Corporate
Segment Reporting Information
Revenue	0	0	0	0
Income (loss) before income taxes	(24,339)	(25,894)	(48,825)	(53,053)
Total assets	$ 703,175	$ 226,535	$ 703,175	$ 226,535