Derivatives and Hedging Activities - Schedule of Changes in AOCI Associated with Derivative Hedging Activities (Details) - Cash flow hedges - USD ($) $ in Millions	12 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2013
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax [Abstract]
Balance, beginning	$ (21.8)	$ (28.5)	$ 7.6	$ (41.5)
Current period changes in fair value, net of tax	(20.8)	(46.0)	36.0
Reclassification to earnings, net of tax	27.5	9.9	13.1
Balance, ending	$ (21.8)	$ (28.5)	$ 7.6