Condensed Consolidated Balance Sheets (Parenthetical) (USD $) In Millions, except Per Share data, unless otherwise specified	Mar. 31, 2013	Jun. 30, 2012
Statement Of Financial Position [Abstract]
Allowance for doubtful accounts	$ 1.9	$ 6.5
Preferred stock, shares authorized	25.0	25.0
Preferred stock, shares issued
Preferred stock, shares outstanding
Common stock, share par value	$ 0.01	$ 0.01
Common stock, share authorized	650.0	650.0
Common stock, share issued	154.4	152.9
Common stock, share outstanding	120.4	124.8
Treasury stock, shares	34.0	28.1