Segment and Geographic Information - Geographic Reporting Segments (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Segment Reporting Information [Line Items]
Net sales	$ 2,452.3us-gaap_SalesRevenueNet	$ 2,300.9us-gaap_SalesRevenueNet
Income (loss) before income taxes	9.1	4.0
Interest expense	0.6us-gaap_InterestExpense	0.7us-gaap_InterestExpense
Depreciation and amortization	8.7	7.2
Capital expenditures	2.7	5.0
Reportable Geographical Components [Member] \| United States
Segment Reporting Information [Line Items]
Net sales	2,176.1	2,039.1
Income (loss) before income taxes	6.5	3.2
Interest expense	8.2	7.5
Depreciation and amortization	6.7	5.5
Capital expenditures	2.6	4.9
Reportable Geographical Components [Member] \| Canada
Segment Reporting Information [Line Items]
Net sales	267.8	256.0
Income (loss) before income taxes	(0.2)	(0.3)
Interest expense	0.2	0.3
Depreciation and amortization	0.6	0.7
Capital expenditures	0.1	0.1
Corporate [Member]
Segment Reporting Information [Line Items]
Net sales	8.4	5.8
Income (loss) before income taxes	2.8	1.1
Interest expense	(7.8)	(7.1)
Depreciation and amortization	$ 1.4	$ 1.0

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391

Reference 2: http://www.xbrl.org/2003/role/presentationRef

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-Topic 942

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

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- Definition

The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3213-108585

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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-Topic 225

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-Subparagraph (SX 210.5-03.1)

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