Note 3 - Assets and Liabilites Measured at Fair Value (Details) - USD ($) $ in Thousands	Jan. 30, 2016	Jan. 31, 2015
Corporate Bond Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash equivalents and short-term investments	$ 7,045	$ 9,283
Corporate Bond Securities [Member]
Cash equivalents and short-term investments	7,045	9,283
Fixed Income Investments [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash equivalents and short-term investments	1,287	1,313
Fixed Income Investments [Member]
Cash equivalents and short-term investments	1,287	1,313
Money Market Funds [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash equivalents and short-term investments	88	7,650
Money Market Funds [Member]
Cash equivalents and short-term investments	88	7,650
Fair Value, Inputs, Level 1 [Member]
Cash equivalents and short-term investments	8,420	18,246
Restricted cash	900	400
Total assets measured at fair value	9,320	18,646
Cash equivalents and short-term investments	8,420	18,246
Restricted cash	900	400
Total assets measured at fair value	$ 9,320	$ 18,646

his element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Company may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. In addition, this item represents short-term investment securities as of the balance sheet date.

No definition available.

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