Investments - Jefferies Finance - Narrative (Details) - USD ($) $ in Thousands	9 Months Ended
Aug. 31, 2024	Nov. 30, 2023
Guarantee Obligations [Line Items]
Other assets	$ 3,263,629	$ 2,650,640
Payables to customers	3,898,469	3,960,557
Jefferies Finance, LLC
Guarantee Obligations [Line Items]
Equity commitment	750,000
Total committed equity capitalization of JFIN	1,500,000
Unfunded portion of equity commitment to subsidiary	$ 15,400
Extension period	1 year
Termination notice period	60 days
Committed line of credit facility amount	$ 500,000
Funded portion of loan commitment	0
Loan commitment	250,000
Jefferies Finance, LLC \| Corporate Joint Venture
Guarantee Obligations [Line Items]
Other assets	2,600	3,500
Payables to customers	$ 3,800	$ 2,600
Jefferies Finance, LLC \| Jefferies Finance, LLC
Guarantee Obligations [Line Items]
Ownership percentage	50.00%

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