Note 4 - Supplemental Financial Information (Details Textual) - USD ($)
$ in Thousands
3 Months Ended
Apr. 29, 2017
Apr. 30, 2016
Jan. 28, 2017
Depreciation, Depletion and Amortization, Nonproduction $ 2,700 $ 3,400  
Property, Plant and Equipment, Net 19,380   $ 18,523
Collaborative Arrangement, Product [Member] | Telechips Inc [Member] | Mask Sets [Member]      
Property, Plant and Equipment, Net $ 2,600