Computation of Basic and Diluted Earnings Per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
Aug. 31, 2018	Aug. 31, 2017	Aug. 31, 2018	Aug. 31, 2017
Numerator:
Net income	$ 12,031	$ 265	$ 198,047	$ 34,765
Denominator:
Weighted average shares outstanding (shares)	44,110,349	44,482,281	44,154,848	44,799,734
Effect of dilutive securities (shares)	8,418	8,997	11,107	12,368
Diluted weighted average shares outstanding (shares)	44,118,767	44,491,278	44,165,955	44,812,102
Basic earnings per share
Basic (in dollars per share)	$ 0.27	$ 0.01	$ 4.49	$ 0.78
Diluted (in dollars per share)	$ 0.27	$ 0.01	$ 4.48	$ 0.78
Anti-dilutive shares excluded in the computation of diluted earnings per share (shares)	26,849	42,486	40,715	58,084

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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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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

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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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