Collateralized Transactions - Collateral Pledged (Details) - USD ($) $ in Thousands	Feb. 29, 2016	Nov. 30, 2015
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	$ 2,670,611	$ 2,979,300
Repurchase Agreements	14,978,982	20,195,982
Total	17,649,593	23,175,282
Corporate equity securities [Member]
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	2,102,900	2,195,912
Repurchase Agreements	169,750	275,880
Total	2,272,650	2,471,792
Corporate debt securities [Member]
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	524,824	748,405
Repurchase Agreements	1,542,462	1,752,222
Total	2,067,286	2,500,627
Mortgage- and asset-backed securities [Member]
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	0	0
Repurchase Agreements	2,956,153	3,537,812
Total	2,956,153	3,537,812
U.S. government and federal agency securities [Member]
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	42,887	34,983
Repurchase Agreements	7,543,014	12,006,081
Total	7,585,901	12,041,064
Municipal securities [Member]
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	0	0
Repurchase Agreements	429,167	357,350
Total	429,167	357,350
Sovereign obligations [Member]
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	0	0
Repurchase Agreements	1,897,266	1,804,103
Total	1,897,266	1,804,103
Loans and other receivables [Member]
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	0	0
Repurchase Agreements	441,170	462,534
Total	$ 441,170	$ 462,534