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Revenue Recognition - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Aug. 31, 2021	Aug. 31, 2020	May 31, 2021
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Deferred commissions, current	$ 80.2		$ 79.4
Deferred commissions, noncurrent	227.2		$ 227.1
Amortization of deferred commissions	$ 21.4	$ 20.4
Revenue \| Product Concentration Risk
Revenue, Initial Application Period Cumulative Effect Transition [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
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Percentage of revenue	95.00%
Uniform Direct Sales \| Revenue \| Product Concentration Risk
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Percentage of revenue	3.20%	2.30%
Uniform Direct Sales \| Revenue \| Product Concentration Risk \| Other
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Percentage of revenue	5.00%