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Revenue Recognition - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Nov. 30, 2023	Nov. 30, 2022	Nov. 30, 2023	Nov. 30, 2022	May 31, 2023
Disaggregation of Revenue [Line Items]
Deferred commissions, current	$ 93.9		$ 93.9		$ 92.5
Deferred commissions, noncurrent	258.6		258.6		$ 251.6
Amortization of deferred commissions	$ 25.2	$ 23.4	$ 49.6	$ 45.8
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	3.60%	3.80%	3.50%	3.80%
Uniform Direct Sales \| Revenue \| Product Concentration Risk \| Other
Disaggregation of Revenue [Line Items]
Percentage of revenue			5.00%