Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Dec. 31, 2019	Jun. 30, 2019
Statement of Financial Position [Abstract]
Allowance for doubtful accounts	$ 10.0	$ 8.8
Accumulated depreciation	$ 266.5	$ 250.8
Preferred stock, par value (in usd per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	50,000,000	50,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in usd per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	650,000,000	650,000,000
Common stock, shares issued (in shares)	160,300,000	160,300,000
Common stock, shares outstanding (in shares)	121,500,000	121,100,000
Treasury stock shares (in shares)	38,800,000	39,200,000