Note 3 - Fair Values of Assets and Liabilities - Assets and Liabilities Measured at Fair Value (Details) - USD ($) $ in Thousands	Jul. 29, 2017	Jan. 28, 2017
Total assets measured at fair value	$ 1,688	$ 8,799
Cash equivalents and short-term investments	1,365	8,496
Restricted cash	323	303
Fair Value, Inputs, Level 1 [Member]
Total assets measured at fair value	1,688	8,799
Cash equivalents and short-term investments	1,365	8,496
Restricted cash	323	303
Money Market Funds [Member]
Cash equivalents and short-term investments	81	3,715
Money Market Funds [Member] | Fair Value, Inputs, Level 1 [Member]
Cash equivalents and short-term investments	81	3,715
Fixed Income Investments [Member]
Cash equivalents and short-term investments	1,284	1,276
Fixed Income Investments [Member] | Fair Value, Inputs, Level 1 [Member]
Cash equivalents and short-term investments	$ 1,284	1,276
Corporate Bond Securities [Member]
Cash equivalents and short-term investments		3,505
Corporate Bond Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Cash equivalents and short-term investments		$ 3,505