Collateralized Transactions - Collateral Pledged (Details) - USD ($) $ in Thousands	May 31, 2024	Nov. 30, 2023
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	$ 2,244,100	$ 1,840,500
Repurchase Agreements	16,848,100	19,841,200
Obligation to Return Securities Received as Collateral, at Fair Value	106,200	8,800
Total	19,198,400	21,690,500
Corporate equity securities
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	1,730,000	1,221,400
Repurchase Agreements	662,400	627,000
Obligation to Return Securities Received as Collateral, at Fair Value	26,200	4,400
Total	2,418,600	1,852,800
Corporate debt securities
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	478,200	576,400
Repurchase Agreements	4,197,300	4,297,900
Obligation to Return Securities Received as Collateral, at Fair Value	0	0
Total	4,675,500	4,874,300
Mortgage-backed and asset-backed securities
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	0	0
Repurchase Agreements	2,052,300	1,950,900
Obligation to Return Securities Received as Collateral, at Fair Value	0	0
Total	2,052,300	1,950,900
U.S. government and federal agency securities
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	26,700	39,200
Repurchase Agreements	6,641,300	9,474,200
Obligation to Return Securities Received as Collateral, at Fair Value	0	3,400
Total	6,668,000	9,516,800
Municipal securities
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	0	0
Repurchase Agreements	467,400	141,100
Obligation to Return Securities Received as Collateral, at Fair Value	0	0
Total	467,400	141,100
Sovereign obligations
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	9,200	3,500
Repurchase Agreements	2,009,400	2,511,600
Obligation to Return Securities Received as Collateral, at Fair Value	80,000	1,000
Total	2,098,600	2,516,100
Loans and other receivables
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	0	0
Repurchase Agreements	818,000	838,500
Obligation to Return Securities Received as Collateral, at Fair Value	0	0
Total	$ 818,000	$ 838,500