Other Non-Current Assets - Schedule of Other Non-Current Assets (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2022	Mar. 31, 2021	Jun. 30, 2021
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
ROU assets	$ 243.0		$ 243.0		$ 262.0
Long-term investments	208.2		208.2		194.0
Deferred sales commissions costs	106.5		106.5		108.6
Contract assets	122.1		122.1		89.8
Long-term broker fees	39.5		39.5		48.7
Deferred data center costs	20.2		20.2		24.3
Other	78.8		78.8		35.0
Total	818.4		818.4		762.5
Deferred client conversion and start-up costs	1,122.3		1,122.3		773.7
Technology	1,113.6		1,113.6		761.7
Deferred sale inducement cost	8.7		8.7		$ 12.0
Amortization of deferred sales commissions and set-up costs	$ 23.8	$ 20.4	$ 74.5	$ 60.2