Summary of Significant Accounting Policies (Details) - USD ($) $ in Millions	12 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Sep. 30, 2020
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Accounting Standards Update [Extensible List]	us-gaap:AccountingStandardsUpdate201613Member	us-gaap:AccountingStandardsUpdate201602Member
Increase to retained earnings	$ 197.6		$ 242.0
Increase in deferred taxes	463.8		$ 467.9
Cumulative Effect, Period of Adoption, Adjustment
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Decrease in allowance for credit loss	(2.8)
Increase to retained earnings	2.1
Increase in deferred taxes	$ 0.7