Segments - Information of total assets for company's reportable segments (Details 1) - USD ($) $ in Thousands		Jul. 31, 2017	Jan. 31, 2017	Jul. 31, 2016
Segment Reporting Information [Line Items]
Total Assets		$ 2,042,051	$ 1,851,944	$ 1,259,520
Corporate
Segment Reporting Information [Line Items]
Total Assets	[1]	151,140	146,333	172,966
Operating Segments | Wholesale
Segment Reporting Information [Line Items]
Total Assets		1,670,243	1,477,259	874,258
Operating Segments | Retail
Segment Reporting Information [Line Items]
Total Assets		$ 220,668	$ 228,352	$ 212,296

[1] Includes assets not allocated to either reportable segment.