Note 7 - Stock-based Compensation - Unvested Option Activity (Details) - Unvested Option [Member] - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	9 Months Ended
Oct. 31, 2018	Jan. 31, 2018
Outstanding at beginning of year (in shares)	31
Outstanding, Weighted average grant date fair value (in dollars per share)	$ 7	$ 8.24
Outstanding at beginning of year, aggregate intrinsic value	$ 23	$ 50
Vested, number (in shares)	(14)
Expired or forfeited (in shares)	(6)
Outstanding at end of period (in shares)	11

For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

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 (c)(1)(iv)(3)-(4)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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- Definition

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

+ References

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-Publisher FASB
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- Definition

Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

+ References

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 (e)(1)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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- Definition

Number of options vested.

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- Definition

The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices.

+ References

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