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Revenue Recognition - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Feb. 29, 2020	Feb. 28, 2019	Feb. 29, 2020	Feb. 28, 2019	May 31, 2019
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Deferred commissions, current	$ 74.5		$ 74.5		$ 69.6
Deferred commissions, noncurrent	221.3		221.3		$ 206.0
Amortization of deferred commissions	$ 19.7	$ 18.0	$ 57.7	$ 52.7
Revenue
Revenue, Initial Application Period Cumulative Effect Transition [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
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%