Stock Options and Warrants - Fair value of common stock (Details) - $ / shares	12 Months Ended
Feb. 29, 2020	Feb. 28, 2019	May 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price			$ 17.50
Expected volatility	50.00%
Expected term (in years)	6 years 3 months	6 years 3 months
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Estimated fair value of common stock	$ 9.55	$ 3.35
Exercise price	$ 18.70	$ 6.75
Expected volatility		50.00%
Riskfree interest rate	2.62%	2.94%
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Estimated fair value of common stock	$ 4.80	$ 2.40
Exercise price	$ 9.60	$ 4.70
Expected volatility		46.00%
Riskfree interest rate	1.67%	2.65%

Agreed-upon price for the exchange of the underlying asset relating to the share-based payment award.

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- Definition

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ 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 (f)(2)(i)
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-Name Accounting Standards Codification
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-Section S99
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-URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809

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