Short-Term Borrowings (Details) - USD ($)	3 Months Ended
	Feb. 29, 2020	Nov. 30, 2019
Short-term Debt [Line Items]
Short-term borrowings	$ 623,156,000	$ 548,490,000
Interest rates on short-term borrowings outstanding	3.23%	3.24%
Equity-linked notes
Short-term Debt [Line Items]
Short-term borrowings	$ 20,164,000	$ 20,981,000
Jefferies Group credit facility
Short-term Debt [Line Items]
Credit facility maximum amount	296,000,000.0
Bank loans
Short-term Debt [Line Items]
Short-term borrowings	602,992,000	$ 527,509,000
Line of credit | Intraday credit facility
Short-term Debt [Line Items]
Credit facility maximum amount	$ 150,000,000.0
Interest rate	0.12%
Line of credit | Intraday credit facility | Base rate
Short-term Debt [Line Items]
Basis spread on variable rate	3.00%
Line of credit | Intraday credit facility | Federal funds effective swap rate
Short-term Debt [Line Items]
Basis spread on variable rate	0.50%