Segment and Geographic Information - Information by Geographic Areas (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Segment Reporting Information [Line Items]
Net sales	$ 3,011.3	$ 2,452.3
Income (loss) before income taxes	9.2	9.1
Interest expense	0.8	0.6
Depreciation and amortization	9.6	8.7
Capital expenditures	8.8	2.7
Reportable Geographical Components | United States
Segment Reporting Information [Line Items]
Net sales	2,736.2	2,176.1
Income (loss) before income taxes	4.9	6.5
Interest expense	9.6	8.2
Depreciation and amortization	7.4	6.7
Capital expenditures	8.5	2.6
Reportable Geographical Components | Canada
Segment Reporting Information [Line Items]
Net sales	269.4	267.8
Income (loss) before income taxes	(0.2)	(0.2)
Interest expense	0.3	0.2
Depreciation and amortization	0.5	0.6
Capital expenditures	0.3	0.1
Corporate
Segment Reporting Information [Line Items]
Net sales	5.7	8.4
Income (loss) before income taxes	4.5	2.8
Interest expense	(9.1)	(7.8)
Depreciation and amortization	$ 1.7	$ 1.4