Compensation Plans - Additional Information (Detail)	9 Months Ended
Aug. 31, 2015 USD ($)
Compensation Related Costs [Abstract]
Vesting period	4 years
Number of years in which restricted stock awards amortized as compensation expense	4 years
Annual employee contributions	$ 21,250
Employee service share based compensation plan stock price	95.00%

Period In Which Restricted Stock Awards Amortized As Compensation Expense

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- Definition

Percentage of closing stock price used to purchase shares under the employee stock purchase plan.

+ References

No definition available.

+ Details

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- Definition

Share based compensation arrangement by maximum employee contributions to employee stock purchase plan.

+ References

No definition available.

+ Details

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- References

No definition available.

+ Details

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ 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)(1)

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

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