Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5047-113901

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- References

No definition available.

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- Definition

Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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Stock-Based Compensation and Stockholders' Rights (Restricted Stock Units) (Details) - Restricted Stock Units (RSUs) [Member] - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Apr. 30, 2017	Apr. 30, 2016	Jan. 31, 2017
Summary of restricted stock and stock unit awards
Expense	$ 167	$ 124
Unrecognized compensation cost	$ 695
2011 Plan [Member]
Summary of restricted stock and stock unit awards
Units granted (units)			87,284
2011 Plan [Member] \| June 21, 2016 [Member] \| 1 year [Member]
Summary of restricted stock and stock unit awards
Units granted (units)	51,284
Terms of vesting	1 year
Expense	$ 50	0
Unrecognized compensation cost	$ 16
2011 Plan [Member] \| June 21, 2016 [Member] \| 3 years [Member]
Summary of restricted stock and stock unit awards
Units granted (units)	36,000
Terms of vesting	3 years
Expense	$ 12	0
Unrecognized compensation cost	$ 96
2011 Plan [Member] \| June 22, 2015 [Member] \| 1 year [Member]
Summary of restricted stock and stock unit awards
Units granted (units)	27,174
Terms of vesting	1 year
Expense	$ 0	19
Unrecognized compensation cost	$ 0
2011 Plan [Member] \| June 22, 2015 [Member] \| 4 years [Member]
Summary of restricted stock and stock unit awards
Units granted (units)	48,000
Terms of vesting	4 years
Expense	$ 8	8
Unrecognized compensation cost	$ 70
2011 Plan [Member] \| June 24, 2014 [Member] \| 1 year [Member]
Summary of restricted stock and stock unit awards
Units granted (units)	28,626
Terms of vesting	1 year
Expense	$ 0	0
Unrecognized compensation cost	$ 0
2011 Plan [Member] \| June 24, 2014 [Member] \| 5 years [Member]
Summary of restricted stock and stock unit awards
Units granted (units)	490,000
Terms of vesting	5 years
Expense	$ 60	60
Unrecognized compensation cost	$ 500
2011 Plan [Member] \| June 19, 2012 [Member] \| 5 years [Member]
Summary of restricted stock and stock unit awards
Units granted (units)	520,000
Terms of vesting	5 years
Expense	$ 37	$ 37
Unrecognized compensation cost	$ 13