EARNINGS PER SHARE (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Nov. 30, 2015	Aug. 31, 2015	May. 31, 2015	Feb. 28, 2015	Nov. 30, 2014	Aug. 31, 2014	May. 31, 2014	Feb. 28, 2014	Nov. 30, 2015	Nov. 30, 2014	Nov. 30, 2013
Earnings Per Share [Abstract]
Net income	$ 32,282	$ (3,956)	$ 13,355	$ 14,953	$ 25,824	$ 191	$ 21,469	$ 19,895	$ 56,634	$ 67,379	$ 45,292
Denominator:
Basic weighted average shares outstanding (in shares)									46,621,211	46,559,232	46,470,647
Common stock options (in shares)									14,619	13,806	15,914
Diluted weighted average shares outstanding (in shares)									46,635,830	46,573,038	46,486,561
Diluted earnings per share:
Basic and diluted earnings per share (in per share)									$ 1.21	$ 1.45	$ 0.97
Anti-dilutive shares excluded in the computation of diluted earnings per share (in shares)									98,928	121,462	143,656