Fair Value Disclosures - Level 3 Rollforwards (Details) - USD ($) $ in Thousands	3 Months Ended
Feb. 28, 2021	Feb. 29, 2020
Assets:
Total gains/losses (realized and unrealized)	$ 12,700	$ (37,900)
Liabilities:
Total gains/losses (realized and unrealized)	72,100	(26,400)
Corporate equity securities
Assets:
Beginning balance	75,797	58,301
Total gains/losses (realized and unrealized)	1,309	(8,195)
Purchases	4,805	2,792
Sales	(4,647)	(1,934)
Settlements	0	0
Issuances	0	0
Net transfers into/ (out of) Level 3	6,014	52,679
Ending balance	83,278	103,643
For instruments still held, changes in unrealized gains/(losses) included in Earnings	135	(8,206)
For instruments still held, changes in unrealized gains/(losses) included in Other comprehensive income	0	0
Liabilities:
Beginning Balance	4,434	4,487
Total gains/losses (realized and unrealized)	9	291
Purchases	0	(513)
Sales	0	0
Settlements	0	0
Issuances	0	0
Net transfers into/ (out of) Level 3	0	10
Ending Balance	4,443	4,275
For instruments still held, changes in unrealized gains/(losses) included in Earnings	(22)	65
For instruments still held, changes in unrealized gains/(losses) included in Other comprehensive income	0	0
Corporate debt securities
Assets:
Beginning balance	23,146	7,490
Total gains/losses (realized and unrealized)	266	1,269
Purchases	130	1,478
Sales	(6)	(503)
Settlements	0	(601)
Issuances	0	0
Net transfers into/ (out of) Level 3	(16,725)	15,957
Ending balance	6,811	25,090
For instruments still held, changes in unrealized gains/(losses) included in Earnings	297	879
For instruments still held, changes in unrealized gains/(losses) included in Other comprehensive income	0	0
Liabilities:
Beginning Balance	141	340
Total gains/losses (realized and unrealized)	1,430	(189)
Purchases	0	(13,832)
Sales	0	14,079
Settlements	0	369
Issuances	0	0
Net transfers into/ (out of) Level 3	0	0
Ending Balance	1,571	767
For instruments still held, changes in unrealized gains/(losses) included in Earnings	(1,430)	(35)
For instruments still held, changes in unrealized gains/(losses) included in Other comprehensive income	0	0
CDOs and CLOs
Assets:
Beginning balance	10,513	20,081
Total gains/losses (realized and unrealized)	3,840	(2,069)
Purchases	11,427	17,594
Sales	(8,007)	(17,833)
Settlements	(5,652)	0
Issuances	0	0
Net transfers into/ (out of) Level 3	13,773	3,179
Ending balance	25,894	20,952
For instruments still held, changes in unrealized gains/(losses) included in Earnings	3,368	(1,823)
For instruments still held, changes in unrealized gains/(losses) included in Other comprehensive income	0	0
RMBS
Assets:
Beginning balance	21,826	17,740
Total gains/losses (realized and unrealized)	1,327	(280)
Purchases	791	0
Sales	(627)	0
Settlements	(514)	(3)
Issuances	0	0
Net transfers into/ (out of) Level 3	(1,111)	(487)
Ending balance	21,692	16,970
For instruments still held, changes in unrealized gains/(losses) included in Earnings	1,347	(250)
For instruments still held, changes in unrealized gains/(losses) included in Other comprehensive income	0	0
CMBS
Assets:
Beginning balance	2,003	6,110
Total gains/losses (realized and unrealized)	(29)	(306)
Purchases	1,105	0
Sales	(393)	0
Settlements	0	(1,401)
Issuances	0	0
Net transfers into/ (out of) Level 3	(15)	(139)
Ending balance	2,671	4,264
For instruments still held, changes in unrealized gains/(losses) included in Earnings	97	571
For instruments still held, changes in unrealized gains/(losses) included in Other comprehensive income	0	0
Liabilities:
Beginning Balance	35	35
Total gains/losses (realized and unrealized)	0	0
Purchases	(35)	0
Sales	35	0
Settlements	0	0
Issuances	0	0
Net transfers into/ (out of) Level 3	0	0
Ending Balance	35	35
For instruments still held, changes in unrealized gains/(losses) included in Earnings	0	0
For instruments still held, changes in unrealized gains/(losses) included in Other comprehensive income	0	0
Other ABS
Assets:
Beginning balance	79,995	42,563
Total gains/losses (realized and unrealized)	2,361	(4,159)
Purchases	14,604	81,323
Sales	(20,909)	(72,032)
Settlements	(8,449)	(1,974)
Issuances	0	0
Net transfers into/ (out of) Level 3	(7,008)	(3,818)
Ending balance	60,594	41,903
For instruments still held, changes in unrealized gains/(losses) included in Earnings	1,721	(3,797)
For instruments still held, changes in unrealized gains/(losses) included in Other comprehensive income	0	0
Loans and other receivables
Assets:
Beginning balance	77,042	64,240
Total gains/losses (realized and unrealized)	1,642	(3,781)
Purchases	8,758	12,940
Sales	(44,427)	(13,042)
Settlements	(66)	(7,087)
Issuances	0	0
Net transfers into/ (out of) Level 3	36,106	1,051
Ending balance	79,055	54,321
For instruments still held, changes in unrealized gains/(losses) included in Earnings	1,656	(5,109)
For instruments still held, changes in unrealized gains/(losses) included in Other comprehensive income	0	0
Investments at fair value
Assets:
Beginning balance	67,108	75,738
Total gains/losses (realized and unrealized)	1,939	(20,392)
Purchases	0	0
Sales	(23,575)	(76)
Settlements	0	0
Issuances	0	0
Net transfers into/ (out of) Level 3	0	0
Ending balance	45,472	55,270
For instruments still held, changes in unrealized gains/(losses) included in Earnings	1,939	(20,392)
For instruments still held, changes in unrealized gains/(losses) included in Other comprehensive income	0	0
Securities purchased under agreements to resell
Assets:
Beginning balance		25,000
Total gains/losses (realized and unrealized)		0
Purchases		0
Sales		0
Settlements		(25,000)
Issuances		0
Net transfers into/ (out of) Level 3		0
Ending balance		0
For instruments still held, changes in unrealized gains/(losses) included in Earnings		0
For instruments still held, changes in unrealized gains/(losses) included in Other comprehensive income		0
Loans
Liabilities:
Beginning Balance	16,635	9,463
Total gains/losses (realized and unrealized)	1,559	1
Purchases	(6,821)	(9,872)
Sales	3,358	2,781
Settlements	0	0
Issuances	0	0
Net transfers into/ (out of) Level 3	185	5,486
Ending Balance	14,916	7,859
For instruments still held, changes in unrealized gains/(losses) included in Earnings	(1,559)	(1)
For instruments still held, changes in unrealized gains/(losses) included in Other comprehensive income	0	0
Net derivatives
Liabilities:
Beginning Balance	26,017	77,168
Total gains/losses (realized and unrealized)	43,727	(17,528)
Purchases	0	(278)
Sales	12,670	5,627
Settlements	(92)	192
Issuances	0	0
Net transfers into/ (out of) Level 3	223,184	45,662
Ending Balance	305,506	110,843
For instruments still held, changes in unrealized gains/(losses) included in Earnings	(43,727)	17,460
For instruments still held, changes in unrealized gains/(losses) included in Other comprehensive income	0	0
Other secured financings
Liabilities:
Beginning Balance	1,543
Total gains/losses (realized and unrealized)	0
Purchases	0
Sales	0
Settlements	0
Issuances	625
Net transfers into/ (out of) Level 3	0
Ending Balance	2,168
For instruments still held, changes in unrealized gains/(losses) included in Earnings	0
For instruments still held, changes in unrealized gains/(losses) included in Other comprehensive income	0
Long-term debt
Liabilities:
Beginning Balance	676,028	480,069
Total gains/losses (realized and unrealized)	25,357	(9,016)
Purchases	0	0
Sales	0	0
Settlements	0	0
Issuances	21,730	128,475
Net transfers into/ (out of) Level 3	0	(56,065)
Ending Balance	723,115	543,463
For instruments still held, changes in unrealized gains/(losses) included in Earnings	15,501	(5,590)
For instruments still held, changes in unrealized gains/(losses) included in Other comprehensive income	$ (40,858)	$ 14,606

Fair Value, Assets Measured On Recurring Basis, Change In Unrealized Gain (Loss) Included In Other Comprehensive Income

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Fair Value, Liabilities Measured On Recurring Basis, Change In Unrealized Gain (Loss) Included In Other Comprehensive Income

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Amount of unrealized gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3) and still held.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3).

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Amount of issuances of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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