NATURE OF BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Nature of Business (Details)	12 Months Ended
	Jan. 31, 2016 segment product location category customer employee
Nature of Business
Number of distinct market sectors in which entity specializes | category	3
Number of operating locations	550
Number of associates | employee	14,000
Number of customer | customer	500,000
Number of SKUs offered | product	850,000
Number of reportable segments | segment	3
U.S.
Nature of Business
Number of states or provinces	48
Canada
Nature of Business
Number of states or provinces	6