Condensed Consolidated Balance Sheets (UNAUDITED) (Parenthetical) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Statement Of Financial Position [Abstract]
Receivables, allowance for doubtful accounts	$ 9.3	$ 7.9
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, authorized	1,000,000.0	1,000,000.0
Preferred stock, Issued	0	0
Common stock, par value	$ 0.01	$ 0.01
Common stock, Authorized	65,000,000.0	65,000,000.0
Common stock, Issued	34,500,000	34,200,000
Treasury stock, Shares	200,000	100,000