Note 3 - Assets and Liabilites Measured at Fair Value (Details) - USD ($) $ in Thousands	Apr. 30, 2016	Jan. 30, 2016
Corporate Bond Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Cash equivalents and short-term investments	$ 7,040	$ 7,045
Corporate Bond Securities [Member]
Cash equivalents and short-term investments	7,040	7,045
Fixed Income Investments [Member] | Fair Value, Inputs, Level 1 [Member]
Cash equivalents and short-term investments	1,302	1,287
Fixed Income Investments [Member]
Cash equivalents and short-term investments	1,302	1,287
Money Market Funds [Member] | Fair Value, Inputs, Level 1 [Member]
Cash equivalents and short-term investments	109	88
Money Market Funds [Member]
Cash equivalents and short-term investments	109	88
Fair Value, Inputs, Level 1 [Member]
Cash equivalents and short-term investments	8,451	8,420
Restricted cash	823	900
Total assets measured at fair value	9,274	9,320
Cash equivalents and short-term investments	8,451	8,420
Restricted cash	823	900
Total assets measured at fair value	$ 9,274	$ 9,320