Corporate Investments and Funds Held For Clients - Expected Maturities of Available-for-Sale Securities (Details) - USD ($) $ in Millions	Jun. 30, 2024	Jun. 30, 2023
Corporate Investments And Funds Held For Clients [Abstract]
One year or less	$ 5,922.2
One year to two years	7,465.5
Two years to three years	5,190.2
Three years to four years	3,857.9
After four years	8,771.7
Total available-for-sale securities	$ 31,207.5	$ 29,764.9