Note 4 - Investments in Privately-held Companies - Value of Investments In Privately-held Companies (Details) - USD ($) $ in Thousands	Feb. 03, 2018	Jan. 28, 2017
Investments		$ 2,000
Issuer A [Member]
Investments		$ 2,000

Amount, after adjustment, of cost-method investment. Adjustments include, but are not limited to, dividends received in excess of earnings after date of investment that are considered a return of investment and other than temporary impairments.

No definition available.

Name:	us-gaap_CostMethodInvestments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant