Investments - Summary of Selected Financial Information for Jefferies Finance (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	May 31, 2019	May 31, 2018	May 31, 2019	May 31, 2018	Nov. 30, 2018
Schedule of Equity Method Investments [Line Items]
CLO placement fee revenues	$ 159,773	$ 158,104	$ 307,099	$ 306,006
Jefferies Finance, LLC
Schedule of Equity Method Investments [Line Items]
Interest income	0	400	0	1,200
Unfunded commitment fees	300	300	600	500
Our total equity balance	643,700		643,700		$ 694,800
Net earnings	50,200	60,200	47,800	102,700
Origination and syndication fee revenues	69,300	109,600	91,200	211,000
Origination fee expenses	8,200	14,900	13,600	33,400
CLO placement fee revenues	0	2,400	1,300	2,700
Derivative losses	0	(300)	0	(600)
Underwriting fees	1,000	0	1,000	300
Service fees	$ 11,200	$ 8,900	$ 38,300	$ 35,000