Accrued Liabilities (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2014	Jun. 30, 2014
Accrued Liabilities
Accrued compensation and benefits	$ 47.7	$ 49.8
Accrued pension liabilities	17.6	19.3
Accrued postretirement benefits	15.5	15.5
Accrued interest expense	5.6	11.2
Deferred revenue	5.9	7.5
Derivative financial instruments	13.0	4.7
Accrued income taxes	2.4	8.4
Other	30.4	31.6
Total accrued liabilities	$ 138.1	$ 148.0