Note 11 - Collaborative Arrangement (Details Textual) - USD ($)
$ in Thousands
3 Months Ended
Apr. 29, 2017
Apr. 30, 2016
Research and Development Expense $ 18,169 $ 19,155
Collaborative Arrangement, Product [Member] | Telechips Inc [Member]    
Collaborative Arrangement, Percentage of Net Profit Receivable as Marketing Service Fee 50.00%  
Net Loss from Collaborative Arrangement $ 100  
Research and Development Expense $ 500