Revenue Recognition - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
May 31, 2021	May 31, 2020	May 31, 2019
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Deferred commissions current	$ 79.4	$ 76.2
Deferred commissions noncurrent	227.1	227.1
Amortization of deferred commissions	$ 83.1	$ 77.8	$ 71.1
Revenue \| Product concentration risk
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Percentage of revenue	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
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Percentage of revenue	95.00%	95.00%
Uniform Direct Sales \| Revenue \| Product concentration risk
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Percentage of revenue	2.70%	4.40%	4.50%
Uniform Direct Sales \| Revenue \| Product concentration risk \| Other
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Percentage of revenue	5.00%	5.00%

Amount of amortization expense for asset recognized from cost incurred to obtain or fulfill contract with customer.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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