Fair Value Disclosures - Financial Assets and Liabilities Accounted for at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Nov. 30, 2021	Nov. 30, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Alternative investment	$ 1,012,322	$ 955,984
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	18,323,915	16,730,068
Counterparty and cash collateral netting	(3,304,566)	(1,556,136)
Securities received as collateral	7,289	7,517
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	11,690,795	10,017,522
Counterparty and Cash Collateral Netting	(3,701,010)	(1,798,659)
Short-term borrowings	0	5,067
Other secured financings	102,788	1,543
Obligation to return securities received as collateral	7,289	7,517
Long-term debt	1,843,598	1,712,245
Corporate equity securities
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	2,843,016	2,465,396
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	1,695,985	2,059,921
Corporate debt securities
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	3,848,106	2,977,347
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	2,112,259	1,237,772
Collateralized debt obligations and collateralized loan obligations
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	611,462	74,668
U.S. government and federal agency securities
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	3,114,079	2,931,678
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	2,457,420	2,609,660
Municipal securities
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	509,559	453,881
Sovereign obligations
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	1,553,285	2,553,688
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	1,528,841	1,675,511
Residential mortgage-backed securities
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	1,169,723	1,122,675
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	719	477
Commercial mortgage-backed securities
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	198,752	738,294
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	210	35
Other asset-backed securities
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	430,546	183,606
Loans and other receivables
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	3,437,635	2,687,788
Derivative, assets
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	568,959	467,817
Investments at fair value
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	38,793	73,230
Loans
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	2,491,857	1,793,081
Net derivatives
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	1,403,504	641,065
Fair value based on net asset value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Alternative investment	1,010,000	956,000
Level 1
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	6,516,500	7,135,334
Securities received as collateral	7,289	7,517
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	5,066,732	5,707,423
Short-term borrowings		0
Other secured financings	0	0
Obligation to return securities received as collateral	7,289	7,517
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	2,567,690	2,331,440
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	1,671,696	2,046,441
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	3,045,295	2,840,025
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	2,457,420	2,609,660
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	899,086	1,962,346
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	935,801	1,050,771
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	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 | Derivative, assets
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	4,429	1,523
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 | Net derivatives
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	1,815	551
Level 2
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	14,775,428	10,771,762
Securities received as collateral	0	0
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	10,225,959	6,039,818
Short-term borrowings		5,067
Other secured financings	76,883	0
Obligation to return securities received as collateral	0	0
Long-term debt	961,866	1,036,217
Level 2 | Corporate equity securities
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	199,244	58,159
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	19,654	9,046
Level 2 | Corporate debt securities
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	3,836,303	2,954,201
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	2,111,777	1,237,631
Level 2 | Collateralized debt obligations and collateralized loan obligations
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	579,518	64,155
Level 2 | U.S. government and federal agency securities
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	68,784	91,653
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	0	0
Level 2 | Municipal securities
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	509,559	453,881
Level 2 | Sovereign obligations
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	654,199	591,342
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	593,040	624,740
Level 2 | Residential mortgage-backed securities
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	1,168,246	1,100,849
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	719	477
Level 2 | Commercial mortgage-backed securities
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	196,419	736,291
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	337,022	103,611
Level 2 | Loans and other receivables
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	3,363,050	2,610,746
Level 2 | Derivative, assets
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	3,858,848	2,000,752
Level 2 | Investments at fair value
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	4,236	6,122
Level 2 | Loans
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	2,476,087	1,776,446
Level 2 | Net derivatives
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	5,024,682	2,391,478
Level 3
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	336,553	379,108
Securities received as collateral	0	0
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	99,114	68,940
Short-term borrowings		0
Other secured financings	25,905	1,543
Obligation to return securities received as collateral	0	0
Long-term debt	881,732	676,028
Level 3 | Corporate equity securities
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	76,082	75,797
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	4,635	4,434
Level 3 | Corporate debt securities
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	11,803	23,146
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	482	141
Level 3 | Collateralized debt obligations and collateralized loan obligations
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	31,944	10,513
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	0
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	1,477	21,826
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	0	0
Level 3 | Commercial mortgage-backed securities
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	2,333	2,003
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	210	35
Level 3 | Other asset-backed securities
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	93,524	79,995
Level 3 | Loans and other receivables
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	74,585	77,042
Level 3 | Derivative, assets
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	10,248	21,678
Level 3 | Investments at fair value
Financial instruments owned:
Total financial instruments owned, excluding Investments at fair value based on NAV	34,557	67,108
Level 3 | Loans
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	15,770	16,635
Level 3 | Net derivatives
Financial instruments sold, not yet purchased:
Financial instruments sold, not yet purchased, at fair value	$ 78,017	$ 47,695