Income Taxes - Components of Provision (Benefit) for Income Taxes (Details) - USD ($) $ in Millions	12 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2023
Current:
Federal	$ 880.5	$ 847.4	$ 840.0
Foreign	136.0	132.8	104.6
State	176.9	177.5	161.1
Total current	1,193.4	1,157.7	1,105.7
Deferred:
Federal	0.7	(18.7)	(77.4)
Foreign	19.4	(6.6)	4.3
State	16.9	(12.1)	(7.0)
Total deferred	37.0	(37.4)	(80.1)
Total provision for income taxes	$ 1,230.4	$ 1,120.3	$ 1,025.6