Income Taxes (Reconciliations of Actual Income Tax Provision and Tax Computed by Applying United States Federal Rate to Earnings Before Income Taxes) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2016	Mar. 31, 2015
Income Tax Disclosure [Abstract]
Expected benefit at the statutory rate	$ (3.9)	$ (25.3)	$ (8.2)	$ (60.9)
Non-deductible stock-based compensation	5.2	8.8	22.6	51.0
State income taxes benefit, net of federal benefit	(0.2)	(3.8)	(0.7)	(8.3)
Transaction costs not deductible for tax purposes	0.6	0.3	1.1	0.6
Foreign tax rate differential	0.5	(0.1)	0.8	0.7
Other, net	5.6	1.7	6.0	3.5
Total provision for income taxes	$ 7.8	$ (18.4)	$ 21.6	$ (13.4)