Note 13 - Equity Incentive Plans and Employee Benefits (Details) - Stock-based Compensation Expense (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Jan. 31, 2015	Feb. 01, 2014	Feb. 02, 2013
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation	$ 6,279	$ 6,814	$ 10,595
Cost of Sales [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation	190	267	487
Research and Development Expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation	3,147	3,381	5,740
Selling and Marketing Expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation	979	1,275	1,811
General and Administrative Expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation	$ 1,963	$ 1,891	$ 2,557