Stock-Based Compensation (Summary of Stock-based Compensation Expense Liability and Equity Classified Awards Included in Consolidated Statements of Operations) (Details) - USD ($) $ in Millions	12 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2015
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 114.1	$ 155.9	$ 200.7
Operating Costs [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation expense	11.3	17.4	23.3
Selling, General and Administrative Expenses [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation expense	102.8	138.5	177.4
Part A Restricted Stock Units [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation expense	76.5	45.3	12.6
Part B Restricted Stock Units [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation expense	26.0	36.5	31.3
Part C Restricted Stock Units [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation expense	1.5	1.1
CII [Member] | Common and Preferred Units [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 10.1	$ 73.0	$ 156.8