CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $) In Millions, except Share data, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Allowance for doubtful accounts on trade receivables	$ 3.5	$ 3.5
Accumulated depreciation on property, plant and equipment	228.9	226.0
Accumulated amortization on intangible assets	$ 31.2	$ 29.7
Class A Common Stock [Member]
Common Stock, par value (usd per share)	$ 0.01	$ 0.01
Common Stock, shares authorized (shares)	900,000,000	900,000,000
Common Stock, shares issued (shares)	49,986,651	49,986,651
Treasury Stock, at cost, shares (shares)	754,853	754,853
Class B Common Stock [Member]
Common Stock, par value (usd per share)	$ 0.01	$ 0.01
Common Stock, shares authorized (shares)	200,000,000	200,000,000
Common Stock, shares issued (shares)	3,125,000	3,125,000
Common Stock, shares outstanding (shares)	3,125,000	3,125,000