Common Shares and Stock-Based Compensation (Performance Shares) - Additional Information (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Feb. 28, 2015	Feb. 28, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share price	$ 19.00us-gaap_SharePrice
Compensation cost recognized		$ 5,721
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance shares granted	Equally divided into three tranches
Share price		$ 19.00
Compensation cost recognized		1,545
Performance Shares [Member] \| Family Shareholders [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Incremental stock based compensation expense		$ 2,603
Minimum [Member] \| Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of performance achievement		0.00%
Maximum [Member] \| Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of performance achievement		200.00%

Represents the achievement percentage of initial shares/units awarded under the performance share plan.

No definition available.

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- Definition

Cumulative effect on previously recognized compensation cost resulting from the modification to a fixed cash settlement value per share.

+ References

No definition available.

+ Details

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- Definition

Additional share-based compensation cost recognized as a result of an occurrence of an event that accelerates its recognition.

+ References

No definition available.

+ Details

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- Details

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- Definition

Description of pertinent provisions of equity-based compensation awards that have actual or potential impact upon the company's financial statements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

+ Details

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Period Type:	instant

- Details

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- Details

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- Details

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