Annual report pursuant to Section 13 and 15(d)

Service Revenue (Summary of PEO Pass-Through Costs Netted in Revenue) (Details)

v3.23.2
Service Revenue (Summary of PEO Pass-Through Costs Netted in Revenue) (Details) - USD ($)
$ in Millions
12 Months Ended
May 31, 2023
May 31, 2022
May 31, 2021
Revenue from Contract with Customer [Abstract]      
Payroll wages and payroll taxes $ 26,025.3 $ 24,209.3 $ 20,706.1
State unemployment insurance (included in payroll wages and payroll taxes) 138.2 139.1 119.0
Guaranteed cost benefit plans $ 656.3 $ 641.4 $ 586.4