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Stockholders' Equity - Stock options outstanding and exercisable (Details) - $ / shares	12 Months Ended
	Feb. 28, 2019	Feb. 28, 2018	Feb. 28, 2017
Number Outstanding	588,000	912,100	839,600
Weighted Average Exercise Price	$ 0.85	$ 0.92	$ 0.89
Number Exercisable	171,000	425,400	395,405
Employee Stock Options | Exercise Price Range $0.61
Range of exercise prices	0.61
Number Outstanding	95,000
Weighted-Average Remaining Life in Years	3 years 9 months
Weighted Average Exercise Price	$ 0.61
Number Exercisable	95,000
Employee Stock Options | Exercise Price Range $0.91 to $0.97
Range of exercise prices, low end (in dollars per share)	$ 0.91
Range of exercise prices, high end (in dollars per share)	$ 0.97
Number Outstanding	243,500
Weighted-Average Remaining Life in Years	7 years 4 months
Weighted Average Exercise Price	$ 0.91
Number Exercisable	2,500
Employee Stock Options | Exercise Price Range $1.05
Range of exercise prices	1.05
Number Outstanding	26,000
Weighted-Average Remaining Life in Years	4 years 11 months
Weighted Average Exercise Price	$ 1.05
Number Exercisable	26,000
Employee Stock Options | Exercise Price Range $1.06
Range of exercise prices	1.06
Number Outstanding	110,000
Weighted-Average Remaining Life in Years	8 years 3 months
Weighted Average Exercise Price	$ 1.06
Number Exercisable
Employee Stock Options | Exercise Price Range $1.07 to $1.67
Range of exercise prices, low end (in dollars per share)	$ 1.07
Range of exercise prices, high end (in dollars per share)	$ 1.67
Number Outstanding	58,500
Weighted-Average Remaining Life in Years	7 years 1 month
Weighted Average Exercise Price	$ 1.27
Number Exercisable	47,500
Employee Stock Options | Exercise Price Range $2.47 to $2.55
Range of exercise prices, low end (in dollars per share)	$ 2.47
Range of exercise prices, high end (in dollars per share)	$ 2.55
Number Outstanding	35,000
Weighted-Average Remaining Life in Years	9 years 10 months
Weighted Average Exercise Price	$ 2.50
Number Exercisable
Employee Stock Options | Exercise Price Range $3.00
Range of exercise prices	3.00
Number Outstanding	20,000
Weighted-Average Remaining Life in Years	9 years 9 months
Weighted Average Exercise Price	$ 3.00

X

- Definition

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.

+ 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 (c)(1)(iii)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

Number of options outstanding, including both vested and non-vested options.

+ 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
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

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-Paragraph 2
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- Definition

The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 718
-SubTopic 10
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- Definition

The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

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-Paragraph 2
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- Definition

Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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