Segment and Geographic Information - Information by Geographic Areas (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Segment Reporting Information [Line Items]
Net sales	$ 3,800.7	$ 3,687.4	$ 7,304.9	$ 6,698.7
Income (loss) before income taxes	11.2	26.4	12.1	35.6
Interest expense	2.0	1.0	4.0	1.8
Depreciation and amortization	12.2	10.2	24.3	19.8
Capital expenditures	17.1	14.0	30.8	22.8
Operating Segment | United States Segment
Segment Reporting Information [Line Items]
Net sales	3,445.2	3,307.1	6,635.3	6,043.3
Income (loss) before income taxes	12.6	29.4	15.6	34.3
Interest expense	10.6	10.2	21.5	19.8
Depreciation and amortization	8.7	7.4	17.4	14.8
Capital expenditures	16.5	13.3	29.9	21.8
Operating Segment | Canada Segment
Segment Reporting Information [Line Items]
Net sales	347.5	373.1	650.6	642.5
Income (loss) before income taxes	2.4	1.3	4.1	1.1
Interest expense	0.2	0.2	0.5	0.5
Depreciation and amortization	0.6	0.7	1.2	1.2
Capital expenditures	0.6	0.7	0.9	1.0
Corporate
Segment Reporting Information [Line Items]
Net sales	8.0	7.2	19.0	12.9
Income (loss) before income taxes	(3.8)	(4.3)	(7.6)	0.2
Interest expense	(8.8)	(9.4)	(18.0)	(18.5)
Depreciation and amortization	$ 2.9	$ 2.1	$ 5.7	$ 3.8