Note 7 - Stock-based Compensation - Unvested Option Activity (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	6 Months Ended
Jul. 31, 2019	Jan. 31, 2019
Outstanding at beginning of period, aggregate intrinsic value	$ 5
Outstanding at end of period (in shares)	3
Outstanding at end of period, weighted average exercise price (in dollars per share)	$ 7.33
Unvested Option [Member]
Outstanding at beginning of period (in shares)	11
Outstanding at beginning of period, weighted average exercise price (in dollars per share)	$ 7
Outstanding at beginning of period, aggregate intrinsic value		$ 19
Vested, number (in shares)	(7)
Expired or forfeited (in shares)	(1)
Expired or forfeited, weighted average exercise price (in dollars per share)	$ 7.99

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=116856206&loc=d3e5070-113901

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Weighted average price of options that were either forfeited or expired.

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

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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.

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-Publisher FASB
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Number of options vested.

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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.

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