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Stockholders' Equity - Stock options outstanding and exercisable (Details) - $ / shares	12 Months Ended
	Feb. 29, 2020	Feb. 28, 2019	Feb. 28, 2018
Number Outstanding	591,667	588,000	912,100
Weighted Average Exercise Price	$ 2.03	$ 0.85	$ 0.92
Number Exercisable	339,250	171,000	425,400
Employee Stock Options | Exercise Price Range $0.61
Range of exercise prices	0.61
Number Outstanding	45,000
Weighted-Average Remaining Life in Years	2 years 9 months
Weighted Average Exercise Price	$ 0.61
Number Exercisable	45,000
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	109,834
Weighted-Average Remaining Life in Years	6 years 3 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	22,500
Weighted-Average Remaining Life in Years	4 years
Weighted Average Exercise Price	$ 1.05
Number Exercisable	22,500
Employee Stock Options | Exercise Price Range $1.06
Range of exercise prices	1.06
Number Outstanding	73,333
Weighted-Average Remaining Life in Years	7 years 2 months
Weighted Average Exercise Price	$ 1.06
Employee Stock Options | Exercise Price Range $1.15 to $1.67
Range of exercise prices, low end (in dollars per share)	1.15
Range of exercise prices, high end (in dollars per share)	$ 1.67
Number Outstanding	48,500
Weighted-Average Remaining Life in Years	6 years 2 months
Weighted Average Exercise Price	$ 1.30
Number Exercisable	44,500
Employee Stock Options | Exercise Price Range $2.10 to $2.65
Range of exercise prices, low end (in dollars per share)	$ 2.10
Range of exercise prices, high end (in dollars per share)	$ 2.65
Number Outstanding	272,500
Weighted-Average Remaining Life in Years	9 years 4 months
Weighted Average Exercise Price	$ 2.54
Number Exercisable	215,750
Employee Stock Options | Exercise Price Range $3.00
Range of exercise prices	3.00
Number Outstanding	20,000
Weighted-Average Remaining Life in Years	8 years 8 months
Weighted Average Exercise Price	$ 3.00
Number Exercisable	9,000

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=120381028&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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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Section 50
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-Name Accounting Standards Codification
-Topic 718
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-URI http://asc.fasb.org/extlink&oid=120381028&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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- 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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- 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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