Revenue (Deferred Costs) (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Mar. 31, 2019		Mar. 31, 2018	Mar. 31, 2019		Mar. 31, 2018	Jun. 30, 2018
Capitalized Contract Cost [Line Items]
Deferred contract costs	$ 2,361.6	[1]		$ 2,361.6	[1]		$ 2,377.4
Amortization of deferred contract costs	220.6		$ 211.2	655.2		$ 623.5
Deferred costs to obtain a contract
Capitalized Contract Cost [Line Items]
Deferred contract costs	919.8			919.8
Deferred costs to fulfill a contract
Capitalized Contract Cost [Line Items]
Deferred contract costs	$ 1,441.8			$ 1,441.8

[1] (1) The amount of total deferred costs amortized during the three and nine months ended March 31, 2019 and March 31, 2018, were $220.6 million and $655.2 million, and $211.2 million and $623.5 million, respectively.