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Revenue Recognition - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Feb. 28, 2019	Feb. 28, 2018	Feb. 28, 2019	Feb. 28, 2018
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Deferred commissions current	$ 68.4		$ 68.4
Deferred commissions noncurrent	203.3		203.3
Amortization of deferred commissions	$ 18.0		$ 52.7
Revenue Recognized under Topic 840
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Concentration risk (as a percent)	100.00%	100.00%	100.00%	100.00%
Uniform Rental and Facility Services \| Revenue Recognized under Topic 840
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Concentration risk (as a percent)	80.70%	80.80%	80.90%	81.20%
Uniform Rental and Facility Services \| Transferred over Time \| Revenue Recognized under Topic 840
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Concentration risk (as a percent)	95.40%		95.60%
First Aid and Safety Services \| Revenue Recognized under Topic 840
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Concentration risk (as a percent)	8.90%	8.70%	8.90%	8.70%
First Aid and Safety Services \| Transferred over Time \| Revenue Recognized under Topic 840
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Concentration risk (as a percent)	90.60%		90.70%
Fire Protection Services \| Revenue Recognized under Topic 840
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Concentration risk (as a percent)	5.90%	5.50%	5.80%	5.30%
Fire Protection Services \| Transferred over Time \| Revenue Recognized under Topic 840
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Concentration risk (as a percent)	100.00%		100.00%
Uniform Direct Sales \| Revenue Recognized under Topic 840
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Concentration risk (as a percent)	4.50%	5.00%	4.40%	4.80%
Uniform Direct Sales \| Transferred at Point in Time \| Revenue Recognized under Topic 840
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Concentration risk (as a percent)	96.30%		96.40%
Uniform Rental and Facility Services, First Aid and Safety Services and Fire Protection Services \| Sales Revenue, Net [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Concentration risk (as a percent)			95.00%
Uniform Direct Sales \| Sales Revenue, Net [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Concentration risk (as a percent)			5.00%