Fair Value Disclosures - Financial Assets and Liabilities Accounted for at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Feb. 28, 2025	Nov. 30, 2024
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Alternative investment	$ 1,366,502	$ 1,252,689
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	24,720,789	22,885,585
Counterparty and cash collateral netting, assets	(3,617,326)	(2,667,751)
Securities segregated and on deposit for regulatory purposes or deposited with clearing and depository organizations	381,467	120,414
Securities received as collateral	287,078	185,588
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	13,997,227	11,007,328
Counterparty and cash collateral netting, liabilities	(3,577,377)	(2,793,713)
Other secured financings	22,231	24,848
Obligation to return securities received as collateral	287,078	185,588
Long-term debt	3,075,403	2,351,346
Corporate equity securities
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	6,672,512	5,779,473
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	4,725,498	3,087,325
Corporate debt securities
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	6,667,029	5,335,746
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	4,370,775	3,105,175
Collateralized debt obligations and collateralized loan obligations
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	1,212,144	1,093,638
U.S. government and federal agency securities
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	2,573,339	3,743,366
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	2,433,696	2,904,405
Municipal securities
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	427,829	320,507
Sovereign obligations
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	1,713,562	1,380,765
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	1,648,508	1,089,771
Residential mortgage-backed securities
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	1,979,371	2,356,576
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	15
Commercial mortgage-backed securities
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	85,408	147,229
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	1,154	1,153
Other asset-backed securities
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	527,920	213,901
Loans and other receivables
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	2,045,118	1,858,738
Derivatives
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	658,668	517,775
Investments at fair value
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	157,889	137,871
Loans
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	139,117	109,185
Derivatives
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	678,464	710,314
Level 1
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	9,707,004	9,571,255
Securities segregated and on deposit for regulatory purposes or deposited with clearing and depository organizations	381,467	120,414
Securities received as collateral	287,078	185,588
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	7,922,920	6,585,916
Other secured financings	0	0
Obligation to return securities received as collateral	287,078	185,588
Long-term debt	0	0
Level 1 | Corporate equity securities
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	6,246,599	5,238,058
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	4,600,182	3,013,877
Level 1 | Corporate debt securities
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	0	0
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	0	0
Level 1 | Collateralized debt obligations and collateralized loan obligations
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	0	0
Level 1 | U.S. government and federal agency securities
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	2,481,241	3,583,139
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	2,433,696	2,904,379
Level 1 | Municipal securities
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	0	0
Level 1 | Sovereign obligations
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	978,901	749,912
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	889,042	667,647
Level 1 | Residential mortgage-backed securities
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	0	0
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	0
Level 1 | Commercial mortgage-backed securities
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	0	0
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	0	0
Level 1 | Other asset-backed securities
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	0	0
Level 1 | Loans and other receivables
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	0	0
Level 1 | Derivatives
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	263	146
Level 1 | Investments at fair value
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	0	0
Level 1 | Loans
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	0	0
Level 1 | Derivatives
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	0	13
Level 2
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	17,849,684	15,247,856
Securities segregated and on deposit for regulatory purposes or deposited with clearing and depository organizations	0	0
Securities received as collateral	0	0
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	9,601,583	7,170,523
Other secured financings	9,526	9,964
Obligation to return securities received as collateral	0	0
Long-term debt	2,214,719	1,529,443
Level 2 | Corporate equity securities
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	213,504	302,051
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	124,726	73,240
Level 2 | Corporate debt securities
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	6,641,104	5,310,815
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	4,369,662	3,105,010
Level 2 | Collateralized debt obligations and collateralized loan obligations
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	1,140,317	1,029,662
Level 2 | U.S. government and federal agency securities
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	92,098	160,227
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	0	26
Level 2 | Municipal securities
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	427,829	320,507
Level 2 | Sovereign obligations
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	734,661	630,681
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	759,466	422,124
Level 2 | Residential mortgage-backed securities
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	1,971,845	2,348,862
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	0
Level 2 | Commercial mortgage-backed securities
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	84,937	146,752
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	0	0
Level 2 | Other asset-backed securities
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	380,601	110,687
Level 2 | Loans and other receivables
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	1,891,354	1,706,152
Level 2 | Derivatives
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	4,271,426	3,181,454
Level 2 | Investments at fair value
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	8	6
Level 2 | Loans
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	138,269	92,321
Level 2 | Derivatives
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	4,209,460	3,477,802
Level 3
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	781,427	734,225
Securities segregated and on deposit for regulatory purposes or deposited with clearing and depository organizations	0	0
Securities received as collateral	0	0
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	50,101	44,602
Other secured financings	12,705	14,884
Obligation to return securities received as collateral	0	0
Long-term debt	860,684	821,903
Level 3 | Corporate equity securities
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	212,409	239,364
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	590	208
Level 3 | Corporate debt securities
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	25,925	24,931
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	1,113	165
Level 3 | Collateralized debt obligations and collateralized loan obligations
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	71,827	63,976
Level 3 | U.S. government and federal agency securities
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	0	0
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	0	0
Level 3 | Municipal securities
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	0	0
Level 3 | Sovereign obligations
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	0	172
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	0	0
Level 3 | Residential mortgage-backed securities
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	7,526	7,714
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	15
Level 3 | Commercial mortgage-backed securities
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	471	477
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	1,154	1,153
Level 3 | Other asset-backed securities
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	147,319	103,214
Level 3 | Loans and other receivables
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	153,764	152,586
Level 3 | Derivatives
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	4,305	3,926
Level 3 | Investments at fair value
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	157,881	137,865
Level 3 | Loans
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	848	16,864
Level 3 | Derivatives
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	46,381	26,212
Fair Value Based on Net Asset Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Alternative investment	$ 1,370,000	$ 1,250,000