Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Aug. 31, 2020	Aug. 31, 2019	Aug. 31, 2020	Aug. 31, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 304,839	$ 49,394	$ 460,405	$ 768,685
Other comprehensive income (loss):
Net unrealized holding gains (losses) on investments arising during the period, net of income tax provision (benefit) of $(7), $58, $141 and $196	(22)	198	411	577
Less: reclassification adjustment for net (gains) losses included in net income, net of income tax provision (benefit) of $0, $0, $0 and $(545,054)	0	0	0	(543,178)
Net change in unrealized holding gains (losses) on investments, net of income tax provision (benefit) of $(7), $58, $141 and $545,250	(22)	198	411	(542,601)
Net unrealized foreign exchange gains (losses) arising during the period, net of income tax provision (benefit) of $24,621, $(9,597), $13,636 and $(12,314)	70,758	(30,070)	35,815	(39,263)
Less: reclassification adjustment for foreign exchange (gains) losses included in net income, net of income tax provision (benefit) of $0,$0, $0 and $0	0	0	0	0
Net change in unrealized foreign exchange gains (losses), net of income tax provision (benefit) of $24,621, $(9,597), $13,636 and $(12,314)	70,758	(30,070)	35,815	(39,263)
Net unrealized gains (losses) on instrument specific credit risk arising during the period, net of income tax provision (benefit) of $(45,669), $1,984, $13,437 and $8,791	(133,915)	5,889	39,373	26,040
Less: reclassification adjustment for instrument specific credit risk (gains) losses included in net income, net of income tax provision (benefit) of $(224), $0, $306 and $(166)	656	0	(898)	493
Net change in unrealized instrument specific credit risk gains (losses), net of income tax provision (benefit) of $(45,445), $1,984, $13,131 and $8,957	(133,259)	5,889	38,475	26,533
Net unrealized gains (losses) on cash flow hedges arising during the period, net of income tax provision (benefit) of $0, $0, $0 and $0	0	0	0	0
Less: reclassification adjustment for cash flow hedges (gains) losses included in net income (loss), net of income tax provision (benefit) of $0, $0, $0 and $161	0	0	0	(470)
Net change in unrealized cash flow hedges gains (losses), net of income tax provision (benefit) of $0, $0, $0 and $(161)	0	0	0	(470)
Net pension gains (losses) arising during the period, net of income tax provision (benefit) of $0, $0, $0 and $0	0	0	0	0
Reclassification adjustment for pension (gains) losses included in net income, net of income tax provision (benefit) of $(220), $(120), $(658) and $(361)	644	355	1,931	1,063
Net change in pension liability, net of income tax provision (benefit) of $220, $120, $658 and $361	644	355	1,931	1,063
Other comprehensive income (loss), net of income taxes	(61,879)	(23,628)	76,632	(554,738)
Comprehensive income	242,960	25,766	537,037	213,947
Comprehensive (income) loss attributable to the noncontrolling interests	324	116	5,033	(759)
Comprehensive (income) loss attributable to the redeemable noncontrolling interests	650	242	1,130	(47)
Preferred stock dividends	(1,404)	(1,275)	(4,230)	(3,827)
Comprehensive income attributable to Jefferies Financial Group Inc. common shareholders	$ 242,530	$ 24,849	$ 538,970	$ 209,314