Consolidated Balance Sheets Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Statement of Financial Position [Abstract]
Allowance for doubtful accounts receivable and returns	$ 18.1	$ 15.7
Amortizable intangible assets, accumulated amortization	203.7	167.1
Debt Issuance cost, unamortized	$ 7.1	$ 7.3
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	25,000,000	25,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares, issued	109,597,197	110,086,283
Common stock, shares outstanding	106,684,084	107,906,644
Treasury stock, shares	2,913,113	2,179,639