CONDENSED CONSOLIDATED STATEMENTS OF INCOME (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Net sales	$ 969.1us-gaap_SalesRevenueGoodsNet	$ 858.8us-gaap_SalesRevenueGoodsNet
Cost of goods sold	816.3us-gaap_CostOfGoodsSold	736.9us-gaap_CostOfGoodsSold
Gross profit	152.8us-gaap_GrossProfit	121.9us-gaap_GrossProfit
Selling, general and administrative expenses	68.5	57.1
Operating income	84.3us-gaap_OperatingIncomeLoss	64.8us-gaap_OperatingIncomeLoss
Interest expense	(25.1)us-gaap_InterestExpense	(25.0)us-gaap_InterestExpense
Investment income	0.8us-gaap_InvestmentIncomeInterest	0.3us-gaap_InvestmentIncomeInterest
Other income, net	2.4us-gaap_OtherNonoperatingIncomeExpense	0.5us-gaap_OtherNonoperatingIncomeExpense
Income before income taxes	62.4	40.6
Income tax expense	9.2us-gaap_IncomeTaxExpenseBenefit	7.0us-gaap_IncomeTaxExpenseBenefit
Net income	$ 53.2us-gaap_ProfitLoss	$ 33.6us-gaap_ProfitLoss
Basic earnings per share	$ 0.69us-gaap_EarningsPerShareBasic	$ 0.44us-gaap_EarningsPerShareBasic
Diluted earnings per share	$ 0.68us-gaap_EarningsPerShareDiluted	$ 0.44us-gaap_EarningsPerShareDiluted

Total costs related to goods produced and sold during the reporting period.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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