Note 7 - Stock-based Compensation - Stock Option Activity (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended	12 Months Ended
Apr. 30, 2022	Jan. 31, 2021	Jan. 31, 2022
Expired or forfeited (in shares)	0
Share-Based Payment Arrangement, Option [Member]
Outstanding (in shares)	67
Outstanding, weighted average exercise price (in dollars per share)	$ 9.51
Outstanding weighted average remaining contractual term (Year)	1 year 7 months 6 days	1 year 8 months 12 days
Outstanding at beginning of period, aggregate intrinsic value	$ 170		$ 63
Exercised (in shares)	(2)
Exercised, weighted average exercise price (in dollars per share)	$ 6.92
Exercised, aggregate intrinsic value	$ 5
Expired or forfeited (in shares)	(1)
Expired or forfeited, weighted average exercise price (in dollars per share)	$ 9.59
Outstanding (in shares)	64
Outstanding, weighted average exercise price (in dollars per share)	$ 9.59
Options exercisable (in shares)	64
Options exercisable, weighted average exercise price (in dollars per share)	$ 9.59
Options exercisable, weighted average remaining contractual term (Year)	1 year 7 months 6 days
Options exercisable, aggregate intrinsic value	$ 170

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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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.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)
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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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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. 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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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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Number of share options (or share units) exercised during the current period.

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