Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Jun. 30, 2018	Jun. 30, 2017
Statement of Financial Position [Abstract]
Allowance for doubtful accounts, current	$ 51.3	$ 49.6
Preferred stock, par value (in dollars per share)	$ 1.00	$ 1.00
Preferred stock, shares authorized	300,000.0	300,000.0
Preferred stock, shares issued	0	0
Common stock, par value (in dollars per share)	$ 0.1	$ 0.1
Common stock, shares authorized	1,000,000,000	1,000,000,000
Common stock, shares issued	638,700,000	638,700,000
Common stock, shares outstanding	438,800,000	445,000,000
Treasury stock, shares	199,900,000	193,700,000
Allowance for doubtful accounts, long-term	$ 0.5	$ 0.8