Investments - Summary of Selected Financial Information for Jefferies Finance (Details) - Jefferies Finance, LLC - USD ($) $ in Millions	3 Months Ended
Feb. 29, 2020	Feb. 28, 2019	Nov. 30, 2019
Schedule of Equity Method Investments [Line Items]
Interest income	$ 0.8	$ 0.0
Unfunded commitment fees	0.3	0.3
Our total equity balance	652.4		$ 642.0
Net earnings (loss)	20.7	(2.4)
Origination and syndication fee revenues	37.7	21.9
Origination fee expenses	5.6	5.4
CLO placement fee revenues	0.4	1.3
Underwriting fees	0.3	0.0
Service fees	$ 25.2	$ 27.1

Fees paid to joint venture related to loan origination.

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Fees paid to joint venture related to loan origination.

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Amount of commission revenue from buying and selling securities on behalf of customers.

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