v2.4.0.6
Collateralized Transactions (Narrative) (Details) (USD $)
In Billions, unless otherwise specified
Dec. 31, 2012
Dec. 31, 2011
Customer margin loans outstanding $ 24.0 $ 16.2
Fair value of financial instruments received as collateral where the Company is permitted to sell or repledge the securities 560 488
Fair value of financial instruments received as collateral where the Company has sold or repledged $ 397 $ 335
Financial instruments, percentage of total assets 12.00%  
Securities collateral, percentage of total assets 24.00%