The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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Sum of operating profit and nonoperating income or expense before Income or Loss from equity method investments, income taxes, extraordinary items, and noncontrolling interest.

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Amount of the cost of borrowed funds accounted for as interest expense.

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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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Segment and Geographic Information - Geographic Reporting Segments (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Segment Reporting Information [Line Items]
Net sales	$ 2,608.6us-gaap_SalesRevenueNet	$ 2,747.4us-gaap_SalesRevenueNet	$ 2,623.2us-gaap_SalesRevenueNet	$ 2,300.9us-gaap_SalesRevenueNet	$ 2,491.3us-gaap_SalesRevenueNet	$ 2,620.7us-gaap_SalesRevenueNet	$ 2,509.9us-gaap_SalesRevenueNet	$ 2,145.7us-gaap_SalesRevenueNet	$ 10,280.1us-gaap_SalesRevenueNet	$ 9,767.6us-gaap_SalesRevenueNet	$ 8,892.4us-gaap_SalesRevenueNet
Income (loss) before income taxes	22.5	20.0	19.9	4.0	23.2	18.9	19.8	4.1	66.4	66.0	55.4
Interest expense	0.6us-gaap_InterestExpense	0.5us-gaap_InterestExpense	0.6us-gaap_InterestExpense	0.7us-gaap_InterestExpense	0.6us-gaap_InterestExpense	0.6us-gaap_InterestExpense	0.8us-gaap_InterestExpense	0.7us-gaap_InterestExpense	2.4us-gaap_InterestExpense	2.7us-gaap_InterestExpense	2.2us-gaap_InterestExpense
Depreciation and amortization	8.6	8.3	7.9	7.2	7.0	6.8	6.8	6.6	32.0	27.2	25.3
Reportable Geographical Components [Member] \| United States [Member]
Segment Reporting Information [Line Items]
Net sales									8,989.0	8,618.3	7,716.3
Income (loss) before income taxes									70.8	57.3	48.6
Interest expense									32.0	30.2	27.4
Depreciation and amortization									24.9	20.2	17.7
Reportable Geographical Components [Member] \| Canada [Member]
Segment Reporting Information [Line Items]
Net sales									1,250.9	1,114.3	1,148.6
Income (loss) before income taxes									3.2	0.9	2.3
Interest expense									0.7	0.6	0.7
Depreciation and amortization									2.8	2.7	2.9
Corporate Eliminations and Adjustments [Member]
Segment Reporting Information [Line Items]
Net sales									40.2	35.0	27.5
Income (loss) before income taxes									(7.6)	7.8	4.5
Interest expense									(30.3)	(28.1)	(25.9)
Depreciation and amortization									$ 4.3	$ 4.3	$ 4.7