Accrued Liabilities (Details) - USD ($) $ in Millions	Mar. 31, 2016	Jun. 30, 2015
Accrued Liabilities, Current [Abstract]
Derivative financial instruments	$ 43.2	$ 32.7
Accrued compensation and benefits	34.8	44.3
Accrued postretirement benefits	14.0	14.0
Accrued interest expense	5.6	11.2
Accrued pension liabilities	3.4	3.3
Accrued income taxes	1.3	8.7
Other	34.9	38.4
Total accrued liabilities	$ 137.2	$ 152.6