Fair Value Measurements (Details 2) (USD $) In Millions, unless otherwise specified	Mar. 31, 2013	Jun. 30, 2012
Carrying Value
Carrying amounts and estimated fair values of financial instruments not recorded at fair value
Long-term debt, including current portion	$ 705.4	$ 406.9
Company-owned life insurance	14.0	11.0
Fair Value
Carrying amounts and estimated fair values of financial instruments not recorded at fair value
Company-owned life insurance	14.0	11.0
Fair Value | Level 2
Carrying amounts and estimated fair values of financial instruments not recorded at fair value
Long-term debt, including current portion	$ 741.1	$ 427.7