CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $) In Millions, except Share data, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Current Assets:
Allowance for doubtful accounts	$ 7.2	$ 5.2
Other Assets:
Accumulated amortization of intangible assets	$ 127.3	$ 83.0
Stockholders' Equity:
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	90,000,000	90,000,000
Common stock, shares issued	15,471,150	15,204,189
Treasury stock, shares	172,685	74,950