Derivative Instruments and Hedging Activities - Offsetting Derivative Assets and Liabilities (Details) - USD ($) $ in Millions	Jun. 30, 2015	Jun. 30, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative asset, gross	$ 60.1	$ 33.8	[1]
Derivative asset, gross liability	(17.2)	(20.1)
Derivative asset, net	42.9	13.7
Cash collateral (received) pledged	0.0	0.0
Derivative asset, net amount recognized in balance sheet	42.9	13.7
Derivative liability, gross	(154.7)	(63.2)	[1]
Derivative liability, gross asset	17.2	20.1
Derivative liability, net	(137.5)	(43.1)
Cash collateral (received) pledged	2.2	0.0
Derivative liability, net amount recognized in balance sheet	$ (135.3)	$ (43.1)

[1] Certain immaterial amounts have been revised to correct the classification of derivatives.