Fair Value Disclosures (Summary of Gains (Losses) Due To Changes In Instrument Specific Credit Risk on Loans, Other Receivables and Debt Instruments Measured at Fair Value Under Fair Value Option) (Details) - USD ($) $ in Thousands	3 Months Ended
	Feb. 29, 2020	Feb. 28, 2019
Fair Value, Option, Quantitative Disclosures [Line Items]
Loans and other receivables	$ 1,739	$ (7,335)
Loans	(610)	0
Loan commitments	(661)	79
Changes in instrument specific credit risk	252	(294)
Long-term Debt:
Fair Value, Option, Quantitative Disclosures [Line Items]
Changes in instrument specific credit risk	29,432	23,483
Other changes in fair value	(37,642)	(10,643)
Short-term borrowings:
Fair Value, Option, Quantitative Disclosures [Line Items]
Changes in instrument specific credit risk	57	0
Other changes in fair value	$ 12	$ 0