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Revenue Recognition - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Nov. 30, 2022	Nov. 30, 2021	Nov. 30, 2022	Nov. 30, 2021	May 31, 2022
Disaggregation of Revenue [Line Items]
Deferred commissions, current	$ 88.2		$ 88.2		$ 83.7
Deferred commissions, noncurrent	244.1		244.1		$ 232.2
Amortization of deferred commissions	$ 23.4	$ 21.7	$ 45.8	$ 43.1
Revenue \| Product Concentration Risk
Disaggregation of Revenue [Line Items]
Percentage of revenue	100.00%	100.00%	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%	3.80%	3.20%
Uniform Direct Sales \| Revenue \| Product Concentration Risk \| Other
Disaggregation of Revenue [Line Items]
Percentage of revenue			5.00%