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Revenue Recognition - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Aug. 31, 2020	Aug. 31, 2019	May 31, 2020
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Deferred commissions, current	$ 77.5		$ 76.2
Deferred commissions, noncurrent	230.0		$ 227.1
Amortization of deferred commissions	$ 20.4	$ 18.8
Revenue
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
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Percentage of revenue	95.00%
Uniform Direct Sales \| Revenue
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Percentage of revenue	5.00%