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Revenue Recognition - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Nov. 30, 2025	Nov. 30, 2024	Nov. 30, 2025	Nov. 30, 2024	May 31, 2025
Disaggregation of Revenue [Line Items]
Deferred commissions, current	$ 96.6		$ 96.6		$ 96.5
Deferred commissions, noncurrent	290.9		290.9		$ 275.3
Amortization of deferred commissions	$ 26.6	$ 26.7	$ 52.8	$ 52.6
Revenue \| Product Concentration Risk
Disaggregation of Revenue [Line Items]
Percentage of revenue	100.00%	100.00%	100.00%	100.00%
Revenue \| Product Concentration Risk \| Uniform Direct Sales
Disaggregation of Revenue [Line Items]
Percentage of revenue	2.90%	3.10%	2.70%	2.70%
Route Servicing Fees \| Revenue \| Product Concentration Risk \| Uniform Rental and Facility Services, First Aid and Safety Services and Fire Protection Services
Disaggregation of Revenue [Line Items]
Percentage of revenue			95.00%
Other \| Revenue \| Product Concentration Risk \| Uniform Direct Sales
Disaggregation of Revenue [Line Items]
Percentage of revenue			5.00%