Income Taxes - Liability For Uncertain Tax Positions (Details) - USD ($) $ in Thousands	Apr. 30, 2017	Jan. 29, 2017
Income Tax Contingency [Line Items]
Liability for UTP	$ 11,480	$ 11,452
Non-current deferred tax asset [Member]
Income Tax Contingency [Line Items]
Liability for UTP	9,309	9,309
Other long-term liabilities [Member]
Income Tax Contingency [Line Items]
Liability for UTP	$ 2,171	$ 2,143