Share Based Awards - Additional Information (Detail) - USD ($)	3 Months Ended
May 31, 2017	May 31, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Fair value assumptions, method used	Black-Scholes-Merton
Share-based compensation expense capitalized	$ 0	$ 0

For each plan, identification of the award pricing model or other valuation method used in calculating the weighted average fair values disclosed. The model is also used to calculate the compensation expense that is shown within the balance sheet, income statement, and cash flow. Examples of valuation techniques are lattice models (binomial model), closed-form models (Black-Scholes-Merton formula), and a Monte Carlo simulation technique. Fair value is the amount at which an asset or liability could be bought or incurred or sold or settled in a current transaction between willing parties, that is, other than in a forced or liquidation sale. May include disclosures about the assumptions underlying application of the method selected.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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