Fair Value Disclosures - Level 3 Rollforwards (Details) - USD ($) $ in Thousands	12 Months Ended
	Nov. 30, 2024	Nov. 30, 2023	Nov. 30, 2022
Assets:
Total gains/(losses) (realized and unrealized)	$ (52,000)	$ 38,500	$ 31,800
Liabilities:
Total gains/(losses) (realized and unrealized)	$ 47,100	$ 62,900	$ (465,700)
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Revenues	Revenues	Revenues
Fair Value, Liability, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Revenues	Revenues	Revenues
Corporate equity securities
Assets:
Beginning balance	$ 181,294	$ 240,347	$ 118,489
Total gains/(losses) (realized and unrealized)	(4,616)	(65,037)	(645)
Purchases	50,297	7,865	171,700
Sales	(524)	(1,228)	(62,474)
Settlements	0	0	(298)
Issuances	0	0	0
Net transfers into/ (out of) Level 3	12,913	(653)	13,575
Ending balance	239,364	181,294	240,347
Changes in unrealized gains/(losses) included in earnings for instruments still held	(11,748)	(11,007)	7,286
Changes in unrealized gains/ (losses) included in other comprehensive income for instruments still held	0	0	0
Liabilities:
Beginning balance	676	750	4,635
Total gains/(losses) (realized and unrealized)	682	348	(3,611)
Purchases	(1,150)	(1,477)	(815)
Sales	0	1,055	4,858
Settlements	0	0	0
Issuances	0	0	0
Net transfers into/ (out of) Level 3	0	0	(4,317)
Ending balance	208	676	750
Changes in unrealized gains/ (losses) included in earnings for instruments still held	3	284	2,382
Changes in unrealized gains/ (losses) included in other comprehensive income for instruments still held	0	0	0
Corporate debt securities
Assets:
Beginning balance	26,112	30,232	11,803
Total gains/(losses) (realized and unrealized)	(4,442)	1,749	946
Purchases	16,219	4,132	18,686
Sales	(7,307)	(18,325)	(23,964)
Settlements	(400)	(200)	(9)
Issuances	0	0	0
Net transfers into/ (out of) Level 3	(5,251)	8,524	22,770
Ending balance	24,931	26,112	30,232
Changes in unrealized gains/(losses) included in earnings for instruments still held	(19,872)	(703)	(2,087)
Changes in unrealized gains/ (losses) included in other comprehensive income for instruments still held	0	0	0
Liabilities:
Beginning balance	124	500	482
Total gains/(losses) (realized and unrealized)	(3)	(35)	88
Purchases	0	(187)	(70)
Sales	0	0	0
Settlements	(1,100)	0	0
Issuances	0	0	0
Net transfers into/ (out of) Level 3	1,144	(154)	0
Ending balance	165	124	500
Changes in unrealized gains/ (losses) included in earnings for instruments still held	105	29	(88)
Changes in unrealized gains/ (losses) included in other comprehensive income for instruments still held	0	0	0
CDOs and CLOs
Assets:
Beginning balance	64,862	55,824	31,946
Total gains/(losses) (realized and unrealized)	(6,194)	31,218	7,099
Purchases	34,964	51,632	44,995
Sales	(21,963)	(3,199)	(22,600)
Settlements	(2,198)	(56,624)	(16,634)
Issuances	0	0	0
Net transfers into/ (out of) Level 3	(5,495)	(13,989)	11,018
Ending balance	63,976	64,862	55,824
Changes in unrealized gains/(losses) included in earnings for instruments still held	(2,437)	(10,774)	(10,938)
Changes in unrealized gains/ (losses) included in other comprehensive income for instruments still held	0	0	0
Sovereign obligations
Assets:
Beginning balance	0
Total gains/(losses) (realized and unrealized)	0
Purchases	172
Sales	0
Settlements	0
Issuances	0
Net transfers into/ (out of) Level 3	0
Ending balance	172	0
Changes in unrealized gains/(losses) included in earnings for instruments still held	172
Changes in unrealized gains/ (losses) included in other comprehensive income for instruments still held	0
RMBS
Assets:
Beginning balance	20,871	27,617	1,477
Total gains/(losses) (realized and unrealized)	(669)	(5,709)	(13,210)
Purchases	6,874	10	35,774
Sales	(5,384)	0	(372)
Settlements	(51)	(247)	(240)
Issuances	0	0	0
Net transfers into/ (out of) Level 3	(13,927)	(800)	4,188
Ending balance	7,714	20,871	27,617
Changes in unrealized gains/(losses) included in earnings for instruments still held	(395)	(1,775)	(7,728)
Changes in unrealized gains/ (losses) included in other comprehensive income for instruments still held	0	0	0
CMBS
Assets:
Beginning balance	508	839	2,333
Total gains/(losses) (realized and unrealized)	(31)	(331)	(733)
Purchases	0	0	0
Sales	0	0	(749)
Settlements	0	0	0
Issuances	0	0	0
Net transfers into/ (out of) Level 3	0	0	(12)
Ending balance	477	508	839
Changes in unrealized gains/(losses) included in earnings for instruments still held	(64)	(327)	(703)
Changes in unrealized gains/ (losses) included in other comprehensive income for instruments still held	0	0	0
Liabilities:
Beginning balance	840	490	210
Total gains/(losses) (realized and unrealized)	(1)	0	0
Purchases	(245)	0	0
Sales	560	350	280
Settlements	0	0	0
Issuances	0	0	0
Net transfers into/ (out of) Level 3	(1)	0	0
Ending balance	1,153	840	490
Changes in unrealized gains/ (losses) included in earnings for instruments still held	1	0	0
Changes in unrealized gains/ (losses) included in other comprehensive income for instruments still held	0	0	0
Other ABS
Assets:
Beginning balance	117,661	94,677	93,524
Total gains/(losses) (realized and unrealized)	(22,251)	(17,800)	(6,467)
Purchases	63,704	71,261	74,353
Sales	(74,139)	(37,088)	(20,362)
Settlements	(10,284)	(26,936)	(39,647)
Issuances	0	0	0
Net transfers into/ (out of) Level 3	28,523	33,547	(6,724)
Ending balance	103,214	117,661	94,677
Changes in unrealized gains/(losses) included in earnings for instruments still held	(17,242)	(20,678)	(26,982)
Changes in unrealized gains/ (losses) included in other comprehensive income for instruments still held	0	0
Loans and other receivables
Assets:
Beginning balance	130,101	168,875	178,417
Total gains/(losses) (realized and unrealized)	(1,664)	10,995	(1,912)
Purchases	79,399	55,520	45,536
Sales	(41,551)	(42,999)	(33,692)
Settlements	(20,523)	(46,383)	(48,218)
Issuances	0	0	0
Net transfers into/ (out of) Level 3	6,824	(15,907)	28,744
Ending balance	152,586	130,101	168,875
Changes in unrealized gains/(losses) included in earnings for instruments still held	(22,108)	4,168	(11,610)
Changes in unrealized gains/ (losses) included in other comprehensive income for instruments still held	0	0	0
Investments at fair value
Assets:
Beginning balance	130,835	161,992	154,373
Total gains/(losses) (realized and unrealized)	(12,142)	83,382	46,735
Purchases	19,726	8,852	74,984
Sales	0	(15,080)	(74,742)
Settlements	(547)	(107,963)	(15,951)
Issuances	0	0	0
Net transfers into/ (out of) Level 3	(7)	(348)	(23,407)
Ending balance	137,865	130,835	161,992
Changes in unrealized gains/(losses) included in earnings for instruments still held	(12,142)	(5,762)	33,294
Changes in unrealized gains/ (losses) included in other comprehensive income for instruments still held	0	0	0
Loans
Liabilities:
Beginning balance	1,521	3,164	9,925
Total gains/(losses) (realized and unrealized)	(148)	(114)	1,197
Purchases	(1,443)	(1,655)	(5,173)
Sales	16,946	126	0
Settlements	0	0	96
Issuances	0	0	0
Net transfers into/ (out of) Level 3	(12)	0	(2,881)
Ending balance	16,864	1,521	3,164
Changes in unrealized gains/ (losses) included in earnings for instruments still held	125	(992)	(2,484)
Changes in unrealized gains/ (losses) included in other comprehensive income for instruments still held	0	0	0
Net derivatives
Liabilities:
Beginning balance	50,955	59,524	67,769
Total gains/(losses) (realized and unrealized)	(9,648)	(10,405)	(181,750)
Purchases	0	(527)	(1,559)
Sales	0	170	1,285
Settlements	(12,298)	(3,496)	0
Issuances	3,766	2,158	28,436
Net transfers into/ (out of) Level 3	(10,489)	3,531	145,343
Ending balance	22,286	50,955	59,524
Changes in unrealized gains/ (losses) included in earnings for instruments still held	8,110	6,760	168,304
Changes in unrealized gains/ (losses) included in other comprehensive income for instruments still held	0	0	0
Other secured financings
Liabilities:
Beginning balance	3,898	1,712	25,905
Total gains/(losses) (realized and unrealized)	4,482	2,186	(650)
Purchases	0	0	0
Sales	0	0	0
Settlements	(4,415)	0	(23,543)
Issuances	10,919	0	0
Net transfers into/ (out of) Level 3	0	0	0
Ending balance	14,884	3,898	1,712
Changes in unrealized gains/ (losses) included in earnings for instruments still held	(4,482)	(2,186)	650
Changes in unrealized gains/ (losses) included in other comprehensive income for instruments still held		0	0
Long-term debt
Liabilities:
Beginning balance	744,597	661,123	881,732
Total gains/(losses) (realized and unrealized)	51,747	70,945	(280,967)
Purchases	0	0	0
Sales	0	0	0
Settlements	(2,109)	0	(3,919)
Issuances	28,614	17,140	83,874
Net transfers into/ (out of) Level 3	(946)	(4,611)	(19,597)
Ending balance	821,903	744,597	661,123
Changes in unrealized gains/ (losses) included in earnings for instruments still held	(37,526)	(28,327)	239,400
Changes in unrealized gains/ (losses) included in other comprehensive income for instruments still held	$ (28,442)	$ (59,706)	$ 41,567