CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $) In Millions, except Share data, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Current assets:
Accounts receivable, allowances	$ 15.5	$ 14.7
Shareholders' equity:
Preferred stock, par value (in dollars per share)	$ 0.01
Preferred stock, shares authorized (in shares)	25
Preferred stock, shares issued (in shares)	0
Common stock, par value (in dollars per share)	$ 0.01
Common stock, shares authorized (in shares)	150
Common stock, shares issued (in shares)	38,861,992	38,861,992
Common stock, shares outstanding (in shares)	36,554,972	36,398,523
Treasury stock (in shares)	2,307,020	2,463,496