Summary of Company Information (Details)	Mar. 31, 2018 center location facility
Revenue from External Customer [Line Items]
Number of customer locations | location	45,000
Number of distribution centers	32
Number of distribution facilities operating as a third party logistics provider | facility	2
United States
Revenue from External Customer [Line Items]
Number of distribution centers	27
Canada
Revenue from External Customer [Line Items]
Number of distribution centers	5