(Certain Unaudited Financial Data For Each Quarter of Fiscal 2011 and 2012) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Nov. 30, 2013	Aug. 31, 2013	May 31, 2013	Feb. 28, 2013	Nov. 30, 2012	Aug. 31, 2012	May 31, 2012	Feb. 29, 2012	Nov. 30, 2013	Nov. 30, 2012	Nov. 30, 2011
Quarterly Financial Information Disclosure [Abstract]
Total revenue	$ 188,668	$ 117,046	$ 178,374	$ 128,552	$ 189,448	$ 115,926	$ 179,595	$ 127,398	$ 612,640	$ 612,367	$ 629,685
Operating income	29,532	(13,067)	37,080	25,147	41,445	696	33,169	29,699	78,692	105,009	133,165
Net income	$ 17,205	$ (7,866)	$ 22,440	$ 13,513	$ 24,736	$ (1,037)	$ 13,740	$ 17,139	$ 45,292	$ 54,578	$ 69,424
Basic and diluted earnings per share	$ 0.37	$ (0.17)	$ 0.48	$ 0.29	$ 0.53	$ (0.02)	$ 0.30	$ 0.37