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 (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Aug. 31, 2019	Aug. 31, 2018	Aug. 31, 2019	Aug. 31, 2018
Financial instruments owned:
Loans and other receivables	$ 2,040	$ 14,002	$ (5,458)	$ 7,495
Long-term debt
Financial instruments sold, not yet purchased and Long-term debt
Changes in instrument specific credit risk	6,922	1,401	34,414	19,986
Other changes in fair value	(46,003)	(6,842)	(93,311)	33,626
Loans
Financial instruments sold, not yet purchased and Long-term debt
Changes in instrument specific credit risk	0	(2,708)	0	(2,467)
Loan commitments
Financial instruments sold, not yet purchased and Long-term debt
Changes in instrument specific credit risk	$ (443)	$ (1,695)	$ (1,200)	$ (1,964)