Computation of Basic and Diluted Earnings Per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
Aug. 31, 2017	Aug. 31, 2016	Aug. 31, 2017	Aug. 31, 2016
Numerator:
Net income	$ 265	$ 2,173	$ 34,765	$ 43,902
Denominator:
Weighted average shares outstanding (shares)	44,482,281	45,720,814	44,799,734	46,189,413
Effect of dilutive securities (shares)	8,997	14,040	12,368	14,550
Diluted weighted average shares outstanding (shares)	44,491,278	45,734,854	44,812,102	46,203,963
Basic and diluted earnings per share
Basic and diluted earnings per share (in dollars per share)	$ 0.01	$ 0.05	$ 0.78	$ 0.95
Anti-dilutive shares excluded in the computation of diluted earnings per share (shares)	42,486	75,068	58,084	85,591

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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- Definition

The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or loss for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

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-Publisher FASB
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- Definition

The sum of dilutive potential common shares or units used in the calculation of the diluted per-share or per-unit computation.

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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