Collateralized Transactions (Contractual Maturity) (Details) - USD ($) $ in Thousands	Feb. 29, 2020	Nov. 30, 2019
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities lending arrangements	$ 1,891,912	$ 1,525,140
Repurchase agreements	18,222,566	18,756,917
Obligation to return securities received as collateral	15,004	9,500
Total	20,129,482	20,291,557
Overnight and Continuous
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities lending arrangements	629,013	694,821
Repurchase agreements	8,025,139	6,614,026
Obligation to return securities received as collateral	5,096	0
Total	8,659,248	7,308,847
Up to 30 Days
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities lending arrangements	83,922	0
Repurchase agreements	2,123,300	1,556,260
Obligation to return securities received as collateral	0	0
Total	2,207,222	1,556,260
31 to 90 Days
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities lending arrangements	1,019,736	672,969
Repurchase agreements	5,978,361	8,988,528
Obligation to return securities received as collateral	9,908	9,500
Total	7,008,005	9,670,997
Greater than 90 Days
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities lending arrangements	159,241	157,350
Repurchase agreements	2,095,766	1,598,103
Obligation to return securities received as collateral	0	0
Total	$ 2,255,007	$ 1,755,453