Leases - Right of Use Assets and Operating Lease Liabilities (Details) - USD ($) $ in Millions	6 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Jun. 30, 2020
Leases [Abstract]
Cash paid for operating lease liabilities	$ 77.0	$ 75.8
Operating lease ROU assets obtained in exchange for new operating lease liabilities	$ 72.0	$ 17.4
Weighted-average remaining lease term (in years)	6 years		6 years
Weighted-average discount rate	2.10%		2.30%
Current operating lease liability	$ 97.4		$ 95.5