Stock Option Plan and Stock Based Compensation - Summary of Unvested Stock Options (Detail) - $ / shares	3 Months Ended
May 31, 2018	May 31, 2017
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Unvested Beginning Balance, Number of Options	1,616
New grants, Number of Options	0	0
Vested, Number of Options	(1,616)
Forfeited, Number of Options	0
Unvested Ending Balance, Number of Options	0
Unvested Beginning Balance, Weighted Average Grant Date Fair Value	$ 2.24
New grants, Weighted Average Grant Date Fair Value	0
Vested, Weighted Average Grant Date Fair Value	2.24
Forfeited, Weighted Average Grant Date Fair Value	0
Unvested Ending Balance, Weighted Average Grant Date Fair Value	$ 0

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- Definition

Gross number of share options (or share units) granted during the period.

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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.

+ 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 (d)(1)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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- Definition

Number of non-vested options outstanding.

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- Definition

Number of non-vested options forfeited.

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Weighted average grant-date fair value of non-vested options forfeited.

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- Definition

Weighted average grant-date fair value of non-vested options outstanding.

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Number of options vested.

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Weighted average grant-date fair value of options vested.

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