Revenue (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Disaggregation of Revenue [Line Items]
Performance obligation	$ 0.0
Accrued sales returns	2.2	$ 1.9
Revenue from contracts with customers	232.2	212.2
United States
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	220.8	202.0
Canada
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	11.4	10.2
Service Revenue
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 0.0	0.0
MRO Products and Industrial Supplies \| Reportable Geographical Components \| United States
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers		202.0
MRO Products and Industrial Supplies \| Reportable Geographical Components \| Canada
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers		$ 10.2
Sales Revenue, Net \| Product Concentration Risk \| Service Revenue
Disaggregation of Revenue [Line Items]
Service revenue, percentage of revenue	1.00%	1.00%

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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