Fair Value Measurements (Details 2) (USD $) In Millions, unless otherwise specified	Sep. 30, 2013	Jun. 30, 2013
Carrying Value
Carrying amounts and estimated fair values of financial instruments not recorded at fair value
Long-term debt, including current portion	$ 604.2	$ 604.2
Company-owned life insurance	13.5	13.6
Fair Value
Carrying amounts and estimated fair values of financial instruments not recorded at fair value
Company-owned life insurance	13.5	13.6
Fair Value | Level 2
Carrying amounts and estimated fair values of financial instruments not recorded at fair value
Long-term debt, including current portion	$ 613.5	$ 602.8