Fair Value Disclosures - Summary of Gains (Losses) Due to Changes in Instrument Specific Credit Risk for Loans and Other Receivables and Loan Commitments Measured at Fair Value under Fair Value Option (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Aug. 31, 2015	Aug. 31, 2014	Aug. 31, 2015	Aug. 31, 2014
Financial instruments owned:
Loans and other receivables	$ (13,566)	$ (15,002)	$ (25,686)	$ (12,841)
Loans [Member]
Financial Instruments Sold:
Loan commitments	38	103	112	(751)
Loan commitments [Member]
Financial Instruments Sold:
Loan commitments	$ (51)	$ 1,338	$ (1,673)	$ (10,299)