Note 14 - Equity Incentive Plans and Employee Benefits - Black-scholes Option Valuation Model Assumptions (Details) - $ / shares	12 Months Ended
Feb. 03, 2018	Jan. 28, 2017	Jan. 30, 2016
Weighted average fair value (in dollars per share)	$ 2.91	$ 3.14	$ 3.64
Employee Stock Option [Member]
Expected Volatility	51.79%	50.77%	44.84%
Risk-free interest rate	1.89%	1.27%	1.60%
Expected term (in years) (Year)	5 years 80 days	5 years 83 days	5 years 69 days
Dividend yield	0.00%	0.00%	0.00%
Weighted average fair value (in dollars per share)	$ 2.91	$ 3.14	$ 3.64
Employee Stock Purchase Plan [Member]
Expected Volatility	38.05%	57.19%	77.90%
Risk-free interest rate	1.13%	0.50%	0.44%
Expected term (in years) (Year)	182 days	182 days	167 days
Dividend yield	0.00%	0.00%	0.00%
Weighted average fair value (in dollars per share)	$ 1.51	$ 1.91	$ 2.24

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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- Definition

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(i)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.D.2)
-URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809

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