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Fair Value Disclosures - Financial Assets and Liabilities Accounted for at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands | Aug. 31, 2025 | Nov. 30, 2024
--- | --- | ---
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Alternative investment | $ 1,499,292 | $ 1,252,689
Financial instruments owned: |  |
Total financial instruments owned, excluding Investments at fair value based on NAV | 24,617,772 | 22,885,585
Counterparty and cash collateral netting, assets | (2,792,740) | (2,667,751)
Securities segregated and on deposit for regulatory purposes or deposited with clearing and depository organizations |  | 120,414
Securities received as collateral | 54,155 | 185,588
Financial instruments sold, not yet purchased: |  |
Financial instruments sold, not yet purchased, at fair value | 12,356,852 | 11,007,328
Counterparty and cash collateral netting, liabilities | (3,151,209) | (2,793,713)
Other secured financings | 611,903 | 24,848
Obligation to return securities received as collateral | 54,155 | 185,588
Long-term debt | 3,564,534 | 2,351,346
Corporate equity securities |  |
Financial instruments owned: |  |
Total financial instruments owned, excluding Investments at fair value based on NAV | 6,215,712 | 5,779,473
Financial instruments sold, not yet purchased: |  |
Financial instruments sold, not yet purchased, at fair value | 4,476,096 | 3,087,325
Corporate debt securities |  |
Financial instruments owned: |  |
Total financial instruments owned, excluding Investments at fair value based on NAV | 5,121,437 | 5,335,746
Financial instruments sold, not yet purchased: |  |
Financial instruments sold, not yet purchased, at fair value | 3,274,941 | 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 | 664,901 | 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 | 3,441,251 | 3,743,366
Financial instruments sold, not yet purchased: |  |
Financial instruments sold, not yet purchased, at fair value | 1,788,901 | 2,904,405
Municipal securities |  |
Financial instruments owned: |  |
Total financial instruments owned, excluding Investments at fair value based on NAV | 518,701 | 320,507
Sovereign obligations |  |
Financial instruments owned: |  |
Total financial instruments owned, excluding Investments at fair value based on NAV | 1,740,538 | 1,380,765
Financial instruments sold, not yet purchased: |  |
Financial instruments sold, not yet purchased, at fair value | 1,488,869 | 1,089,771
Residential mortgage-backed securities |  |
Financial instruments owned: |  |
Total financial instruments owned, excluding Investments at fair value based on NAV | 1,450,756 | 2,356,576
Commercial mortgage-backed securities |  |
Financial instruments owned: |  |
Total financial instruments owned, excluding Investments at fair value based on NAV | 83,927 | 147,229
Financial instruments sold, not yet purchased: |  |
Financial instruments sold, not yet purchased, at fair value | 1,189 | 1,153
Other asset-backed securities |  |
Financial instruments owned: |  |
Total financial instruments owned, excluding Investments at fair value based on NAV | 814,754 | 213,901
Loans and other receivables |  |
Financial instruments owned: |  |
Total financial instruments owned, excluding Investments at fair value based on NAV | 2,671,803 | 1,858,738
Derivatives |  |
Financial instruments owned: |  |
Total financial instruments owned, excluding Investments at fair value based on NAV | 1,732,485 | 517,775
Investments at fair value |  |
Financial instruments owned: |  |
Total financial instruments owned, excluding Investments at fair value based on NAV | 161,507 | 137,871
Loans |  |
Financial instruments sold, not yet purchased: |  |
Financial instruments sold, not yet purchased, at fair value | 73,580 | 109,185
Derivatives |  |
Financial instruments sold, not yet purchased: |  |
Financial instruments sold, not yet purchased, at fair value | 1,253,276 | 710,314
Level 1 |  |
Financial instruments owned: |  |
Total financial instruments owned, excluding Investments at fair value based on NAV | 10,136,074 | 9,571,255
Securities segregated and on deposit for regulatory purposes or deposited with clearing and depository organizations |  | 120,414
Securities received as collateral | 54,155 | 185,588
Financial instruments sold, not yet purchased: |  |
Financial instruments sold, not yet purchased, at fair value | 7,057,129 | 6,585,916
Other secured financings | 0 | 0
Obligation to return securities received as collateral | 54,155 | 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 | 5,737,635 | 5,238,058
Financial instruments sold, not yet purchased: |  |
Financial instruments sold, not yet purchased, at fair value | 4,432,279 | 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 | 3,354,090 | 3,583,139
Financial instruments sold, not yet purchased: |  |
Financial instruments sold, not yet purchased, at fair value | 1,788,871 | 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 | 1,043,729 | 749,912
Financial instruments sold, not yet purchased: |  |
Financial instruments sold, not yet purchased, at fair value | 835,790 | 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
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 | 620 | 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 | 189 | 13
Level 2 |  |
Financial instruments owned: |  |
Total financial instruments owned, excluding Investments at fair value based on NAV | 16,471,572 | 15,247,856
Securities segregated and on deposit for regulatory purposes or deposited with clearing and depository organizations |  | 0
Securities received as collateral | 0 | 0
Financial instruments sold, not yet purchased: |  |
Financial instruments sold, not yet purchased, at fair value | 8,401,811 | 7,170,523
Other secured financings | 595,789 | 9,964
Obligation to return securities received as collateral | 0 | 0
Long-term debt | 2,493,370 | 1,529,443
Level 2 | Corporate equity securities |  |
Financial instruments owned: |  |
Total financial instruments owned, excluding Investments at fair value based on NAV | 205,768 | 302,051
Financial instruments sold, not yet purchased: |  |
Financial instruments sold, not yet purchased, at fair value | 43,021 | 73,240
Level 2 | Corporate debt securities |  |
Financial instruments owned: |  |
Total financial instruments owned, excluding Investments at fair value based on NAV | 5,087,057 | 5,310,815
Financial instruments sold, not yet purchased: |  |
Financial instruments sold, not yet purchased, at fair value | 3,274,453 | 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 | 612,592 | 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 | 87,161 | 160,227
Financial instruments sold, not yet purchased: |  |
Financial instruments sold, not yet purchased, at fair value | 30 | 26
Level 2 | Municipal securities |  |
Financial instruments owned: |  |
Total financial instruments owned, excluding Investments at fair value based on NAV | 518,701 | 320,507
Level 2 | Sovereign obligations |  |
Financial instruments owned: |  |
Total financial instruments owned, excluding Investments at fair value based on NAV | 696,809 | 630,681
Financial instruments sold, not yet purchased: |  |
Financial instruments sold, not yet purchased, at fair value | 653,079 | 422,124
Level 2 | Residential mortgage-backed securities |  |
Financial instruments owned: |  |
Total financial instruments owned, excluding Investments at fair value based on NAV | 1,442,778 | 2,348,862
Level 2 | Commercial mortgage-backed securities |  |
Financial instruments owned: |  |
Total financial instruments owned, excluding Investments at fair value based on NAV | 83,421 | 146,752
Financial instruments sold, not yet purchased: |  |
Financial instruments sold, not yet purchased, at fair value | 1 | 0
Level 2 | Other asset-backed securities |  |
Financial instruments owned: |  |
Total financial instruments owned, excluding Investments at fair value based on NAV | 688,579 | 110,687
Level 2 | Loans and other receivables |  |
Financial instruments owned: |  |
Total financial instruments owned, excluding Investments at fair value based on NAV | 2,531,881 | 1,706,152
Level 2 | Derivatives |  |
Financial instruments owned: |  |
Total financial instruments owned, excluding Investments at fair value based on NAV | 4,516,818 | 3,181,454
Level 2 | Investments at fair value |  |
Financial instruments owned: |  |
Total financial instruments owned, excluding Investments at fair value based on NAV | 7 | 6
Level 2 | Loans |  |
Financial instruments sold, not yet purchased: |  |
Financial instruments sold, not yet purchased, at fair value | 71,614 | 92,321
Level 2 | Derivatives |  |
Financial instruments sold, not yet purchased: |  |
Financial instruments sold, not yet purchased, at fair value | 4,359,613 | 3,477,802
Level 3 |  |
Financial instruments owned: |  |
Total financial instruments owned, excluding Investments at fair value based on NAV | 802,866 | 734,225
Securities segregated and on deposit for regulatory purposes or deposited with clearing and depository organizations |  | 0
Securities received as collateral | 0 | 0
Financial instruments sold, not yet purchased: |  |
Financial instruments sold, not yet purchased, at fair value | 49,121 | 44,602
Other secured financings | 16,114 | 14,884
Obligation to return securities received as collateral | 0 | 0
Long-term debt | 1,071,164 | 821,903
Level 3 | Corporate equity securities |  |
Financial instruments owned: |  |
Total financial instruments owned, excluding Investments at fair value based on NAV | 272,309 | 239,364
Financial instruments sold, not yet purchased: |  |
Financial instruments sold, not yet purchased, at fair value | 796 | 208
Level 3 | Corporate debt securities |  |
Financial instruments owned: |  |
Total financial instruments owned, excluding Investments at fair value based on NAV | 34,380 | 24,931
Financial instruments sold, not yet purchased: |  |
Financial instruments sold, not yet purchased, at fair value | 488 | 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 | 52,309 | 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 | 7,978 | 7,714
Level 3 | Commercial mortgage-backed securities |  |
Financial instruments owned: |  |
Total financial instruments owned, excluding Investments at fair value based on NAV | 506 | 477
Financial instruments sold, not yet purchased: |  |
Financial instruments sold, not yet purchased, at fair value | 1,188 | 1,153
Level 3 | Other asset-backed securities |  |
Financial instruments owned: |  |
Total financial instruments owned, excluding Investments at fair value based on NAV | 126,175 | 103,214
Level 3 | Loans and other receivables |  |
Financial instruments owned: |  |
Total financial instruments owned, excluding Investments at fair value based on NAV | 139,922 | 152,586
Level 3 | Derivatives |  |
Financial instruments owned: |  |
Total financial instruments owned, excluding Investments at fair value based on NAV | 7,787 | 3,926
Level 3 | Investments at fair value |  |
Financial instruments owned: |  |
Total financial instruments owned, excluding Investments at fair value based on NAV | 161,500 | 137,865
Level 3 | Loans |  |
Financial instruments sold, not yet purchased: |  |
Financial instruments sold, not yet purchased, at fair value | 1,966 | 16,864
Level 3 | Derivatives |  |
Financial instruments sold, not yet purchased: |  |
Financial instruments sold, not yet purchased, at fair value | 44,683 | 26,212
Fair value based on net asset value |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Alternative investment | $ 1,500,000 | $ 1,250,000

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