Revenue Recognition - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
May 31, 2022	May 31, 2021	May 31, 2020
Disaggregation of Revenue [Line Items]
Deferred commissions current	$ 83.7	$ 79.4
Deferred commissions noncurrent	232.2	227.1
Amortization of deferred commissions	$ 87.4	$ 83.1	$ 77.8
Revenue from Contract with Customer Benchmark \| Product concentration risk
Disaggregation of Revenue [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 from Contract with Customer Benchmark \| Product concentration risk \| Route servicing fees
Disaggregation of Revenue [Line Items]
Percentage of revenue	95.00%	95.00%
Uniform Direct Sales \| Revenue from Contract with Customer Benchmark \| Product concentration risk
Disaggregation of Revenue [Line Items]
Percentage of revenue	3.40%	2.70%	4.40%
Uniform Direct Sales \| Revenue from Contract with Customer Benchmark \| Product concentration risk \| Other
Disaggregation of Revenue [Line Items]
Percentage of revenue	5.00%

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

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