Deferred Client Conversion and Start-Up Costs - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2024	Dec. 31, 2023	Jun. 30, 2024
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Deferred client conversion and start-up costs	$ 863.8		$ 863.8		$ 892.1
Deferred client conversion and start-up costs	856.9		856.9		884.5
Other start-up costs	6.8		6.8		$ 7.6
Amortization of deferred sales commissions costs	$ 38.1	$ 32.2	$ 74.7	$ 64.4