Earnings Per Share (Basic and Diluted Earnings (Loss) Per Share) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Feb. 29, 2016	Feb. 28, 2015
Earnings Per Share [Abstract]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	9,700	8,200
Numerator:
Net income	$ 13,127	$ 7,799
Less: Distributed earnings allocated to nonvested restricted stock	(10)	(9)
Less: Undistributed earnings allocated to nonvested restricted stock	(50)	(20)
Numerator for basic earnings per share	13,067	7,770
Interest expense and amortization of debt issuance costs associated with convertible senior notes, net of taxes	667	667
Add: Undistributed earnings allocated to nonvested restricted stock	50	20
Less: Undistributed earnings reallocated to nonvested restricted stock	(45)	(18)
Numerator for diluted earnings per share	$ 13,739	$ 8,439
Denominator:
Weighted average shares outstanding — basic	89,239	91,954
Effect of dilutive securities: Share-based payments	1,786	1,344
Effect of dilutive securities: Convertible senior notes	8,402	8,402
Weighted average shares outstanding — diluted	99,427	101,700
Basic earnings per share, in dollars per share	$ 0.15	$ 0.08
Diluted earnings per share, in dollars per share	$ 0.14	$ 0.08