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Revenue (Details) - USD ($) $ in Millions	3 Months Ended			6 Months Ended		12 Months Ended
Revenue (Details) - USD ($) $ in Millions	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Disaggregation of Revenue [Line Items]
Performance obligation	$ 0.0			$ 0.0
Accrued sales returns	2.5			2.5
Revenue from contracts with customers	363.1		$ 313.0	718.3	$ 615.5	$ 1,265.4
Reportable Geographical Components \| United States
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	220.4		194.6	422.4	377.2
Reportable Geographical Components \| Canada
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	10.8		8.1	21.0	15.7
Reportable Geographical Components \| France
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	131.9		$ 110.3	274.9	$ 222.6
Service Revenue
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers		$ 0.0
MRO Products and Industrial Supplies \| Reportable Geographical Components \| United States
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	220.4			422.4
MRO Products and Industrial Supplies \| Reportable Geographical Components \| Canada
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	10.8			21.0
Technology Products \| France
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	125.9			262.8
Technology Products \| Other Europe
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 6.0			$ 12.1
Sales Revenue, Net \| Product Concentration Risk \| Service Revenue
Disaggregation of Revenue [Line Items]
Service revenue, percentage of revenue		1.00%