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Revenue Recognition - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Aug. 31, 2022	Aug. 31, 2021	May 31, 2022
Disaggregation of Revenue [Line Items]
Deferred commissions, current	$ 86.1		$ 83.7
Deferred commissions, noncurrent	239.2		$ 232.2
Amortization of deferred commissions	$ 22.4	$ 21.4
Revenue \| Product Concentration Risk
Disaggregation of Revenue [Line Items]
Percentage of revenue	100.00%	100.00%
Uniform Rental and Facility Services, First Aid and Safety Services and Fire Protection Services \| Revenue \| Product Concentration Risk \| Route Servicing Fees
Disaggregation of Revenue [Line Items]
Percentage of revenue	95.00%
Uniform Direct Sales \| Revenue \| Product Concentration Risk
Disaggregation of Revenue [Line Items]
Percentage of revenue	3.80%	3.20%
Uniform Direct Sales \| Revenue \| Product Concentration Risk \| Other
Disaggregation of Revenue [Line Items]
Percentage of revenue	5.00%