Significant Accounting Policies - Deferred Revenue (Details) - USD ($) $ in Thousands	Jan. 28, 2018	Jan. 29, 2017
Deferred Revenue Arrangement [Line Items]
Deferred revenue	$ 12,758	$ 12,059
Deferred Revenues [Member]
Deferred Revenue Arrangement [Line Items]
Deferred revenue	9,794	11,419
Deferred Cost of Revenues [Member]
Deferred Revenue Arrangement [Line Items]
Deferred revenue	(2,189)	(2,246)
Deferred Revenue, Net [Member]
Deferred Revenue Arrangement [Line Items]
Deferred revenue	7,605	9,173
Deferred Product Design and Engineering Recoveries [Member]
Deferred Revenue Arrangement [Line Items]
Deferred revenue	$ 5,153	$ 2,886