Commitments, Contingencies and Guarantees - Additional Information (Details) $ in Millions	9 Months Ended
	Aug. 31, 2022 USD ($)
Loss Contingencies [Line Items]
Loss contingency accrual	$ 80.0
Fair value of derivative contracts approximated deemed to meet the definition of a guarantee	768.8
Standby letters of credit
Loss Contingencies [Line Items]
Letters of credit commitments	$ 13.1
Standby letters of credit | Maximum
Loss Contingencies [Line Items]
Standby letters of credit expiration period	1 year
Outstanding loan commitments to clients
Loss Contingencies [Line Items]
Loan commitments outstanding to clients	$ 100.4
Jefferies Capital Partners LLC
Loss Contingencies [Line Items]
Outstanding equity commitments	10.7
Oak Hill
Loss Contingencies [Line Items]
Outstanding equity commitments	69.7
Strategic Affiliates
Loss Contingencies [Line Items]
Outstanding equity commitments	415.8
Other Investments
Loss Contingencies [Line Items]
Outstanding equity commitments	$ 35.6