Investments - Jefferies Finance - Narrative (Details) - Jefferies Finance, LLC $ in Millions	6 Months Ended
May 31, 2022 USD ($) businessLine	Nov. 30, 2021 USD ($)
Guarantee Obligations [Line Items]
Number of business lines \| businessLine	2
Equity commitment	$ 750.0
Total committed equity capitalization of JFIN	1,500.0
Unfunded portion of equity commitment to subsidiary	$ 15.4
Extension period	1 year
Termination notice period	60 days
Funded portion of loan commitment	$ 0.0
Loan commitment	250.0
Other assets
Guarantee Obligations [Line Items]
Receivables under service agreement	3.0	$ 26.2
Accrued expense and other liabilities
Guarantee Obligations [Line Items]
Due to related parties	0.8	$ 8.5
Corporate debt securities
Guarantee Obligations [Line Items]
Committed line of credit facility amount	$ 500.0
Jefferies Finance, LLC
Guarantee Obligations [Line Items]
Ownership percentage	50.00%

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