Segments - Information of total assets for company's reportable segments (Details 1) - USD ($) $ in Thousands	Apr. 30, 2018	Jan. 31, 2018	Apr. 30, 2017
Segment Reporting Information [Line Items]
Total Assets	$ 2,040,563	$ 1,915,177	$ 1,803,788
Corporate
Segment Reporting Information [Line Items]
Total Assets	173,374	145,418	139,622
Operating Segments | Wholesale
Segment Reporting Information [Line Items]
Total Assets	1,655,714	1,554,191	1,459,142
Operating Segments | Retail
Segment Reporting Information [Line Items]
Total Assets	$ 211,475	$ 215,568	$ 205,024