Summary of Significant Accounting Policies - Amortization of Property and Equipment Using Declining Balance Method (Detail)	12 Months Ended
	Jan. 28, 2018
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, amortization rate	20.00%
Computer hardware | Minimum
Property, Plant and Equipment [Line Items]
Property and equipment, amortization rate	20.00%
Computer hardware | Maximum
Property, Plant and Equipment [Line Items]
Property and equipment, amortization rate	30.00%
Equipment and vehicles
Property, Plant and Equipment [Line Items]
Property and equipment, amortization rate	30.00%