Summary of Significant Accounting Policies - Additional Information (Details) $ in Millions	12 Months Ended							36 Months Ended
	Jun. 30, 2020 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2020 USD ($) segment	Jun. 30, 2020 USD ($)	Jun. 30, 2020 USD ($) Segment	Jun. 30, 2019 USD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2019 USD ($)	Jul. 01, 2019 USD ($)	Jun. 30, 2017 USD ($)
Property, Plant and Equipment [Line Items]
Number of reportable segments			2		2
Investment securities maturity period for consideration as cash equivalents, in days	90 days
Inventory	$ 21.5	$ 21.5	$ 21.5	$ 21.5	$ 21.5	$ 21.1		$ 21.1
Advertising costs		6.8				4.1	$ 6.3
Operating lease liability recognized	323.5	323.5	323.5	323.5	323.5				$ 252.0
Operating lease right-of-use asset recognized	292.6	292.6	292.6	292.6	292.6				$ 235.4
Retained earnings	2,302.6	2,302.6	2,302.6	2,302.6	2,302.6	2,087.7		2,087.7
Cumulative effect of changes in accounting principle	$ 1,346.5	$ 1,346.5	$ 1,346.5	$ 1,346.5	$ 1,346.5	1,127.5	1,094.3	1,127.5		$ 1,003.8
Accounting Standards Update 2016-02
Property, Plant and Equipment [Line Items]
Accounting Standards Update [Extensible List]	us-gaap:AccountingStandardsUpdate201602Member
Accounting Standards Update 2014-09
Property, Plant and Equipment [Line Items]
Accounting Standards Update [Extensible List]	us-gaap:AccountingStandardsUpdate201409Member
Cumulative Effect, Period of Adoption, Adjustment
Property, Plant and Equipment [Line Items]
Cumulative effect of changes in accounting principle						$ 0.2	$ 101.3	$ 0.2
Software and Software Development Costs | Minimum
Property, Plant and Equipment [Line Items]
Estimated useful lives of assets	3 years
Software and Software Development Costs | Maximum
Property, Plant and Equipment [Line Items]
Estimated useful lives of assets	5 years
Five Largest Customers | Customer Concentration Risk | Revenue Benchmark [Member]
Property, Plant and Equipment [Line Items]
Percentage of consolidated revenues				20.00%		22.00%	21.00%
Largest Customer | Customer Concentration Risk | Revenue Benchmark [Member]
Property, Plant and Equipment [Line Items]
Percentage of consolidated revenues								6.00%