Annual report pursuant to Section 13 and 15(d)

Funds Held for Clients and Corporate Investments (Realized Gains and Losses from Sale of Available-for-sale Securities) (Details)

v3.22.2
Funds Held for Clients and Corporate Investments (Realized Gains and Losses from Sale of Available-for-sale Securities) (Details) - USD ($)
$ in Millions
 12 Months Ended
May 31, 2022
May 31, 2021
May 31, 2020
Funds Held for Clients and Corporate Investments [Abstract]      
Gross realized gains $ 0.2 $ 1.2 $ 11.6
Gross realized losses 0.0   (0.3)
Net realized gains on available-for-sale securities $ 0.2 $ 1.2 $ 11.3