Segment Information - Information Related to Operating Segments (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Feb. 28, 2019	Feb. 28, 2018	Feb. 28, 2019	Feb. 28, 2018	Jun. 01, 2018	May 31, 2018
Segment Reporting Information
Revenue	$ 1,682,330	$ 1,589,138	$ 5,098,573	$ 4,807,082
Income (loss) before income taxes	251,555	174,507	813,499	599,959
Total assets	7,433,673	6,928,593	7,433,673	6,928,593	$ 7,211,341	$ 6,958,214
Operating Segments \| Uniform Rental and Facility Services
Segment Reporting Information
Revenue	1,358,322	1,284,516	4,124,038	3,904,338
Income (loss) before income taxes	239,138	173,287	713,563	596,011
Total assets	6,451,590	5,900,987	6,451,590	5,900,987
Operating Segments \| First Aid and Safety Services
Segment Reporting Information
Revenue	149,170	137,327	455,935	416,999
Income (loss) before income taxes	21,622	16,705	64,933	54,091
Total assets	508,865	472,982	508,865	472,982
Operating Segments \| All Other
Segment Reporting Information
Revenue	174,838	167,295	518,600	485,745
Income (loss) before income taxes	17,495	10,032	40,627	34,232
Total assets	392,359	368,368	392,359	368,368
Corporate
Segment Reporting Information
Revenue	0	0	0	0
Income (loss) before income taxes	(26,700)	(25,517)	(5,624)	(84,375)
Total assets	$ 80,859	$ 186,256	$ 80,859	$ 186,256

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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